Ago/Before vs. In…(time)/After

1. Counting from now vs. a set time

A common mistake non-native English speakers make is when measuring between two times.

  • When measuring between two times, people use ‘before’ or ‘after’.
  • However, when one of the times is now, people use ‘ago’ or ‘in…time’.

2. Ago vs. before

‘Ago’ measures time before now.

Time 1Time 2Example sentence
NowNow – 2 minutesShe heard the news 2 minutes ago.
NowNow – 5 yearsI came to Shanghai 5 years ago.
NowNow – 20 yearsHe graduated 20 years ago.

‘Before’ measures time before another event. ‘Before’ structures must have two different events.

Time 1Time 2Example sentence
He came to ShanghaiHe came to Shanghai – 2 monthsI came to Shanghai 2 months before he did.
I met herI met her – one yearHe graduated one year before I met her.
Your game will be playedYour game will be played – xOur game will be played before yours.

3. In…time vs. after

‘In…time’ measures time after now.
*Note: ‘In…time’ can be shortened to ‘in…’.

Time 1Time 2Example sentence
Nownow + 3 monthsI will change jobs in 3 months time.
Nownow + 5 minutesHe will go home in 5 minutes.
Nownow + 10 yearsJulia will retire in 10 years time.

‘After’ measures time after another event. ‘After’ structures must have two different events.

Time 1Time 2Example sentence
I ate dinnerI ate dinner + 5 minutesI felt sick 5 minutes after I ate dinner.
He changed jobHe changed job + 2 weeksI changed jobs 2 weeks after he did.
He finishes workHe finishes work + xHe will go home after he finishes his work.

4. Exercises

1. Answer these questions:
(i) What did you do 2 days ago?
(ii) What are you going to do in 5 hours time?
(iii) What did you do before you ate breakfast today?
(iv) What are you going to do after you retire?

2. Describe what you did/will do on these days:
(i) Today (using ‘ago’ and ‘in…time’)
(ii) Yesterday (using ‘before’ and ‘after’)