NEED(N´T), DON´T HAVE TO AND MUSTN´T

Mustn´t and needn´t / don´t have to
We use mustn´t to say that something is not allowed and needn´t (or don´t need to) or don´t have to to say that something is not necessary:
* You mustn´t walk on the grass here.
* You mustn´t put anything on the shelves until the glue has set hard.
* They proved that watchig a chess match needn´t be boring.
* We needn´t go into details now, but we seem to agree on the general principles.

Need, needn´t, and don´t need to / don´t have to
Need can be used as a modal verb (before a bare infinitive) or as an ordinary verb. Compare:
* You needn´t speak so loudly. (= modal verb)
* She needn´t come with us if she doesn´t want to. (= modal verb)
* She´s thirsty. She needs a drink. (= ordinary verb)
* Jim and Bob are here. They say they need to see you urgently. (= ordinary verb)
When it is a modal verb need is most commonly used in negative sentences, although it is sometimes also used in questions:
* Need you go home so soon? (or, more commonly, Do you have to...?)
* Need I say more? (or, more commonly, Do I have to say...?)

We can use either needn´t or don´t have to when we say that is unnecessary to do something:
* It would be good to see you, but you needn´t (or don´t have to) come if you´re busy.
* You needn´t (or don´t have to) whisper. Nobody can hear us.

To give permission not to do something we can use either needn´t or don´t need to:
* You needn´t cut the grass, I´ll do it later.
* You don´t need to cut the grass, I´ll do it later.

To talk about a general necessity, we prefer don´t need to:
* You don´t need to be over 18 to get into a disco.

Didn´t need to / didn´t have to and need not have
When we say that it was not necessary to do something in the past, and it wasn´t done, we use didn´t need to or didn´t have to. To show that we think something that was done was not, in fact, necessary we use need not have:
* Chris and June phoned to say that they couldn´t come to eat, so I didn´t need/have to cook dinner. (= I didn´t cook dinner)
* I needn´t have cooked dinner. Just as it was ready, Chris and June phoned to say that they couldn´t come to eat. (= I did cook dinner)

Source: Advanced Grammar in Use - Martin Hewings - Cambridge.

NEED, NEEDN´T, DON´T NEED TO...

NEEDN´T (NEED NOT)

I needn´t (do something) = it is not necessary to do it, I don´t need to do it:
* I needn´t clean the windows. They aren´t very dirty.
* You needn´t go to the bank today. I can give you some money.

You can also say don´t need to... (= needn´t)
* I don´t need to clean the windows.
* You don´t need to go to the bank today.

Source: Essential Grammar in Use - Raymond Murphy - Cambridge




NEEDN´T
You needn´t do something" - it is not necessary that you do it, you don´t need to do it.
* You can come with me if you like, but you needn´t come if you don´t want to. (= it is not necessary for you to come.)
* We´ve got plenty of time. We needn´t hurry. (= it is not necessary to hurry)

Instead of needn´t, you can use don´t/doesn´t need to. So you can say:
* We needn´t hurry.     or      We don´t need to hurry.
Remember that we say "don´t need to do", but "needn´t do" (without to)

Needn´t and don´t need to are similar to don´t have to
* We´ve got plenty of time. We don´t have to hurry.


NEEDN´T HAVE (DONE)
* That shirt isn´t dirty. You needn´t wash it.
* Why did you wash that shirt? It wasn´t dirty. You needn´t have washed it.


Didn´t need to (do) and needn´t have (done)

I didn´t need to ... = it was not necessary for me to... (and I knew this at the time):
* I didn´t need to get up early, so I didn´t.
* I didn´t need to get up early, but it was a lovely morning, so I did.

I needn´t have (done) something = I did something but now I know that it was not necessary.
* I got up very early because I had to get ready to go away. But in fact it didn´t take me long to get ready. So, I needn´t have got up so early. I could have stayed in bed longer.

Source: English Grammar in Use - Raymond Murphy - Cambridge

2nd CONDITIONAL

2nd. Conditional: tentative, hypothetical, and unreal conditions (present or future time reference)


If we caught the 10 o´clock train, we would (could, might, etc) get there by lunchtime.
If I came into a fortune, I would give up working.
If I knew how it worked, I could tell you what to do.

Exercise: complete the sentences

If you explained the situation to your solicitor, he .............................................................................
Perhaps he ............................................................, if you spoke to him yourself.
If you changed your job, you............................................................................................................
If you went to see a doctor, he ........................................................................................................
If we bought a house in the country, we ...........................................................................................
If they came to see us in London, we ...............................................................................................
I´m sure he would take the job on if ................................................................................................
If you took the shoes back to the shop, they ....................................................................................
If you read the book a second time, you ..........................................................................................

Exercise: answer the questions with conditional statements (2nd)

What cities or other places of interest would you visit if you went to America?
What would you do (or not do) if you could live your life again?
What would you say or do if someone called you a fool?
If a visitor came to your town, what places would you advise him to see?
What famous person would you like to meet if you had the chance?
Which country would you choose if you decided to live abroad?
What changes would you make in your house, assuming you had the money?
What would you do if you saw a house on fire?
What would you do if you had something stolen?
Which books would you take with you if you went to live on a desert island?

Exercise: Turn the following sentences into 2nd conditional:
Example: We don´t have any wood, so we can´t light a fire. If we had some wood, we could light a fire.

Since she doesn´t love him, she won´t marry him.
Our teacher explains things clearly, so we understand his lessons.
As I haven´t a watch, I casn´t tell you the time.
Britain doesn´t export enough, so she has a constant balance of payments problem.
Since I know the meaning of the word, I don´t have to look it up.
This exercise is easy, so everyone will get the correct answers.
I know the answer so I can tell you.
We haven´t any matches so we can´t light the fire.

wish, would rather, It´s time + noun clause with past tense:
I wish I were rich (If only I were rich!)
I´d rather you told me frankly what you think.
It´s time (it´s about time, it´s high time) we left.
I wish you would hurry up.
I wish it would stop raining soon.

Source: Advanced English Practice - B.D. Graver - Oxford

WAYS OF EXPRESSING THE FUTURE

For plans and arrangements:

I´m doing something tomorrow. - I´ve arranged, I´ve planned to do it.
I´m going to a concert tomorrow.
Alice is going to the dentist on Friday. (She has an appointment)
We are having a party next weekend. (Everything has already been planned.)

Decision, intention to to something:

I´m going to do something. - I´ve decided to do it, my intention is to do it.
I´m going to buy some new books tomorrow.
Sarah is going to sell her car.
I´m not going to have breakfast this morning. I´m not hungry.

Something is going to happen; it´s clear now that it´s sure to happen:

Look at the sky! It´s going to rain!

will/shall - Simple future

Sue travels a lot. Today she´s in Madrid. Tomorrow she´ll be in Rome. Next week she´ll be in Tokyo.
You can phone me this evening. I´ll be at home.
We will probably go out tonight.
I won´t be here tomorrow.

Don´t drink coffee before you go to bed. You won´t sleep.
I think I will pass the exam.
I don´t think it will rain this afternoon.
Do you think the exam will be difficult?

Also used when you offer or decide to do something:

'My bag is very heavy.' - 'I´ll carry it for you.'
'Bye! I´ll phone you tomorow!'
(the phone rings) - 'I´ll answer it!'

Shall (you can say 'I shall' (= I will) and 'we shall' (= we will)

Do not use shall with you/they/he/she/it:
Tom will be late.


Shall I/we...? = Do you think this is a good thing to do? Do you think this is a good idea?
It´s warm in the room. Shall I open the window?
I´m going to a party tonight. What shall I wear?
It´s a nice day. Shall we go for a walk?
Where shall we go for our holidays this year?

Present Simple with a future meaning: we use the present simple when we talk about timetable, programmes, etc... (e.g. for public transport, cinema, etc...)
The train leaves Plymouth at 11:30 and arrives in London at 12:45.
What time does the film begin?
It´s Wednesday tomorrow.

We can use the present simple for people if their plans are fixed like a timetable:
I start my new job on Monday.
What time do you finish work tomorrow?

Source: Essential Grammar in Use - Raymond Murphy - Cambridge

TOO AND ENOUGH

TOO: used before adjectives and adverbs; to a higher degree or more than it´s allowed, desirable, good, necessary, etc...

Don´t drive too fast.
It´s too good to be true!
These shoes are too small for me.
The journey is too long, we will get tired.

ENOUGH: usually used in front of plural or uncountable nouns; as many or as much of something as necessary or desirable; sufficient.

Have you made enough copies?
There are twenty students and only 12 chairs.There aren´t enough chairs for all the students.
Surely 15 minutes is enough time for you to have a bath.
Is there enough room for me in the car?
He hasn´t got enough money to buy a sandwich.

ENOUGH + NOUN
- Is there enough sugar in your coffee?
- We wanted to play football but we didn´t have enough players.
- Don´t you have enough money to buy a car?

ADJECTIVE + ENOUGH
- It isn´t warm enough to stay outside.
- Is the radio loude enough for you?
- That coat isn´t long enough.
- He isn´t tall enough to reach the shelf.

ENOUGH WITHOUT A NOUN
- I´ve got some money, but not enough to buy a car.
- I don´t want anything else. I´ve had enough.
- I don´t go out enough.

SO AND SUCH

SO (THAT) + adjectives / adverbs

I was so well this morning that I stayed longer in bed.
I was so tired this morning that I stayed longer in bed.

SO + little / few / much / many

There was so little money left that I decided not to travel.
There were so few passengers that the flight was cancelled.

There was so much problem with the computer that the company bought a new one.
There were so many songs in the MP3 that it was difficult to listen to all of them.


SUCH + plural nouns and uncountable nouns

They were such nice people!
We have such beautiful weather in Limeira!
He wears such nice clothes.
He writes such interesting books!

SUCH A / AN + singular nouns

We`ve had such a nice meal.
Ann is such a nice person!
It was such an unusual scene!
It´s such an ugly city.
I´ve got such a lot of things to do.

I didn´t enjoy the book. The story was so stupid.
I didn´t enjoy the book. It was such a stupid story!

FIRST CONDITIONAL - OPEN CONDITIONS

Ex: If we catch the 10 o´clock train, we shall (can, may, etc...) get there by lunchtime.
      If you wake up before me, give me a call.

In the above sentences, the conditional clauses represent "open" conditions; that is, conditions that may or may not be fulfilled. We make such statements when the action or event mentioned in the conditional clause is being actively considered, or is under discussion or appears likely to happen. Such statements can enen be comments or decisions already taken.

Conditions of this sort are sometimes labelled "probable", but it is important to note that the probability of the condition being fulfilled often exists only in the mind of the speaker. If, for example, it seems likely that someone is going to do something foolish or dangerous, we give a warning: "If you touch that plate, you´ll burn your hand." Only a fool would fulfill the condition in these circumstances.

The commonest sequence of tenses in this type of sentence is:
(If) present tense, (Main) future or modal verb or imperative.

Exercise: write conditional sentences like the ones above, using the given fact, and adding a suitable completion, eg. If he goes to England, he will have to learn English.

It looks as if those shoes in the window are my size.
Don´t drop the vase!
It looks like being fine tomorrow.
My father has suggested that I change my job.
It seems that we´ll be late for the cinema.
Don´t lose my library book!
You may meet some friends of mine in London.
He expects to pass his exam.
They´re hoping it will be a baby boy.
I anticipate getting a rise in salary next year.

Exercise: complete the sentences, following one of the patterns for contditionals of type 1:
We will just manage to catch the train if............................................................................
If I see him again, I .........................................................................................................
I will accept your explanation only if ...............................................................................
If my bank manager will lend me the money, ...................................................................
What will happen if ........................................................................................................
If you don´t hear from me by next Friday, ......................................................................
If your work continues to improve, ................................................................................
................................................................. only if you will promise not to tell anyone else.
Look up the answeer in the key only id...........................................................................
What will he say if .........................................................................................................
If the worst should come to the worst, ...........................................................................
Give me time and ..........................................................................................................

Source: Advanced English Practice - B.D. Graver - Oxford.

Some more examples:
If she can´t come to see us, then we´ll have to go and see her.
If we go by bus, it will be cheaper. (It will be cheaper if we go by bus.)
If you don´t hurry, we will miss the train. (We will miss the train if you don´t hurry.)
If I don´t feel well tomorrow, I will stay home.
If you pass the exam, you will get a certificate.

If you get a high paying job, you won´t have to work as hard.
If you get a high paying job, you´ll be able to travel first class.
If you get a high paying job, you might have to pay higher taxes.
If you get a high paying job, you´ll be able to donate more to charities.
If you get a high paying job, you´ll be able to buy things you want.
If you get a high paying job, you might be on TV or in the newspapers.
If you get a high paying job, people will ask you for a loan.
If you get a high paying job, you will have more free time.
If you get a high paying job, you´ll be able to buy your parents a new car.

If you don´t have to work as hard, you´ll have a lot more free time.
If you eat less sugar, you may feel more relaxed.
If you eat less sugar, you might feel healthier.
If you walk to work everyday, you might feel healthier.
If you walk to work everyday, you may feel more relaxed.
If you wak to work everyday, you´ll stay in shape without joining a gym.
If you don´t get enough sleep, you won´t be able to stay awake in class.
If you own a pet, you may feel more relaxed.
If you don´t get married, you will have more money to spend on yourself.
If you eat less sugar, you´ll lose weight.

If you buy a large dog, you´ll have to take it out for walks everyday.
If you take it out for walks everyday, you might have an accident.
If you have an accident, you may have to go to the hospital.
If you go to the hospital, you won´t be able to take care of your dog,
If you aren´t able to take care of your dog, you´ll probably have to give it away.

If yo fall in love, you´ll feel jealous sometimes.
If you fall in love, you will feel better about yourself.
If you go on a diet, you´ll feel hungry a lot.
If you go on a diet, you´ll have to give up your favourite snack.
If you inherit a lot of money, you´ll be able to buy expensive clothes.
If you inherit a lot of money, you´ll get requests for loans.
If you move to a foreign country, you´ll have to learn a new lnaguage.
If you move to a foreign country, you´ll lose touch with old friends.

Sources> several books.