We use since with the starting point. Examples: since January, since Monday, since last year.
We use for with a period of time. Examples: for two hours, for weeks, for ages.
In negative sentences, we can use in and for with the same meaning.
Fill in the blanks with for, since or in.
1I haven't seen him ............... months.
Select 2 answers.
Wrong!
In negative present perfect sentences, both "in" and "for" can be used before a period of time such as months.
2He has been absent ............... several days.
Wrong!
Use "for" with a period of time such as several days.
3They have lived here ............... their whole lives.
Wrong!
Use "for" with a period of time such as their whole lives.
4This has been going on ............... several months.
Wrong!
Use "for" with a period of time such as several months.
5He has been unwell ............... he moved to the city.
Wrong!
Use "since" before a clause that gives the starting point of a state or action.
6Have you been waiting ............... long?
Wrong!
Use "for" in the question phrase "for long".
7It hasn't rained ............... months.
Select 2 answers.
Wrong!
In negative present perfect sentences, both "in" and "for" can be used before a period of time such as months.
8I have known him ............... a long time.
Wrong!
Use "for" with a period of time such as a long time.
9We have known each other ............... our childhood.
Wrong!
Use "since" with a starting point such as our childhood.
10I haven't been to the theatre ............... ages.
Select 2 answers.
Wrong!
In negative present perfect sentences, both "for" and "in" can be used before a period of time such as ages.
11She has been acting ............... she was three.
Wrong!
Use "since" before a clause that gives the starting point of an action.
12I have been teaching English ............... twenty years.
Wrong!
Use "for" with a period of time such as twenty years.
Done.
Score: 0/12
Answers
- I haven’t seen him in / for months.
- He has been absent for several days.
- They have lived here for their whole lives.
- This has been going on for several months.
- He has been unwell since he moved to the city.
- Have you been waiting for long?
- It hasn’t rained in / for months.
- I have known him for a long time.
- We have known each other since our childhood.
- I haven’t been to the theatre for / in ages.
- She has been acting since she was three.
- I have been teaching English for twenty years.

