Languages Focus

Question tags

A question tag is a short interrogative phrase to a statement.
It's cold (statement)
isn't it? (tag).

Negative tags are added to positive statements and positive tags to negative statements.
It's not cold, is it?

The question tag repeats the auxiliary verb or modal auxiliary verb from the statement, and the subject pronoun. If there is no auxiliary verb in the statement, do is used:
You like oranges, don't you?

There are exceptions, for example, imperatives:
Sit down, will you?
Please help, won't you?

Future in the past

These forms are used when we take a point in the past and talk about what happened after that.

When he was six, everyone knew he was going to be a footballer.
He went on to play in the school team.
He was to appear in a total of thirty-four international matches before he retired.

Uses of do

Do is an auxiliary verb that is used to form questions and negatives.

Do you know the time?
I'm sorry I don't know the time.

Do can be used to avoid repeating a longer phrase.
I don't like ice-cream, but my sister does.

Do is also used in positive statements to give emphasis to the verb.
Oh, I do like your new dress. (Really, I'm not just being polite!)
I do work hard at school. (I know you think I don't.)

must -- have to

must
Must is nearly only used in writing forms and in external obligations by law and in official language. Must is used only in the present.
Avoid to use must in personal speech!
You mustn't smoke here.
have to
Have to is used in personal speech.
I have to get up early everyday.
In the past you can use only had to (must is not possible):
When I was a child, I had to wear a uniform at school.