Learn English :: Los Angeles Serbs

until and unless

Until and unless can be used together in this complimentary way, Anil, as a sort of set phrase, but the meaning of these two conjunctions is, of course different.

until / till = up to a particular point in time

Note from these examples that until and till can be used both as conjunctions and prepositions and that till is the informal equivalent of until:

You are unlikely to earn decent money until you start working hard.
I won't start the project till I hear that all the plans have been approved.

She resigned in March but continued to draw her salary till the end of May.
Please wait in the waiting room until they call your name.

unless = if not x, then y

We use unless to indicate that if something does not happen, something else will happen as a result of this:

I shall not refund you your money unless you send me the original receipt.
I can't help you, unless you tell me what's wrong.

Because the ideas contained within if not x, then y and up to a particular moment in time are complimentary, we can link the two by saying until and unless or unless and until:

I can't refund you your money until and unless you send me original receipts.
I can't start work on this project unless and until the plans are approved.

Note that present tenses are used with both until and unless to indicate future time.

In all of the above examples, Fatima, unless refers to present and future situations. It is sometimes used with past simple and present perfect, but not as frequently. In these examples of use, unless introduces an afterthought:

- Where's Brian?

- I don't know. He should still be here - unless he went home early.

- Where are my tennis shoes?

- They should be in the shoe box - unless you've left them at the club.

When unless is used as an alternative to if... not in conditional sentences, it may sometimes be used with the present perfect, which is, of course, linked to the present, or, occasionally, with a range of past tenses:

Unless you've tried it for yourself, you can't imagine how relaxing it is.

If you've never tried it, you have no idea how relaxing a jacuzzi can be.

You never hear him express an opinion in seminar discussion, unless he's thought very carefully about the topic.

If he hasn't thought carefully about it, he remains absolutely silent.

We normally walked to work, unless we were going shopping afterwards, in which case we'd take the car.

Unless you had seen it with your own eyes, you wouldn't have believed that such a thing could happen.

Kevin never ate kebabs, unless he had prepared them himself.