Ответ:

Упражнение 1

B It has been raining since this morning

C They have been playing tennis for 30 minutes

D They have been walking on the mountain for 5 hours

упражнение 2

A for

B since

C for

D since

E since

F since

G for

H since

I since

J since

K for

L for

M for

Упражнение 3

2 since Thursday

3 since you left school

4 since this morning

5 since he was born

6 since 1990

7 for twenty minutes

8 for twenty years

Объяснение: