Раскрыть скобки и выбрать подходящее время. 

1) have been
2) decided
3) has heard
4) were
5) slept
6) have written
7) wasn't
8) haven't finished
9) drank, was
10) hasn't got
11) hasn't got
12) didn't decide
13) haven't told (либо didn't tell - нет временных указателей)
14) unvited
15) has come
16) has just had
17) have had
18) has explained
19) had
20) got