Present tense: when, before, after, until, etc.

1. Look at this sentence:

When the programme ends, I'll do the washing- up.


To talk about an event in the future, we usually use the Present Simple (e.g. ends) after when, before, after, until and as soon as. We do not use will:

I'm going to finish this work before I go.

(Not ... before I will go)

Wait here until I get back.

I'll phone you as soon as I arrive.


2. We can use when + Present Simple to referto a time when something will happen:

I'll buy an ice - cream when I'm in the newsagent's


now -------------------------------------------------> future

in the newsagent's

buy an ice- cream


When you see her, give her my message.


We use until + Present Simple to mean from now to a time in the future:

We'll sit outside until it gets dark. ( = We'll sit outside from now to when it gets dark.)


We use as soon as + Present Simple with the meaning "inmediatly after":

They'll start playing as soon as it stops raining. (= They'll start playin inmediatly after the rain stops.)


3. We use when + Present Perfect (e.g I have done) to talk about an action that must, or will, happen before the next action can happen:

When I've found a job, I'll book for a place to live. (= First I will find a job; then i will look for a place to live.)


now ------------------------------------------------------------ future

find a job look for a flat

When Simon has saved enough money, he'll buy a car. (= First Simon must save the money; then he can buy a car.)

4. With after we can use either the Present Simple or the Present perfect with no difference in meaning:

After she takes/ has taken the course, she'll be qualified teacher. (= When she has done her course, she'll be qualified teacher.)