1 had left
2 swam
3 has been
4 have played -was
5 have used - bought
6 will do
7 had visited
8 were sleeping
9 will get
10 have learnt
11 used to
12 was reading
13 had returned
14 finishes
15 used
16 discovered
17 have readed
18 was cooking
19 had studied
20 had just left
1 had left
2 swam
3 has been
4 have played -was
5 have used - bought
6 will do
7 had visited
8 were sleeping
9 will get
10 have learnt
11 used to
12 was reading
13 had returned
14 finishes
15 used
16 discovered
17 have readed
18 was cooking
19 had studied
20 had just left