11 joined - was
12 has painted
13 discovered
14 have studied - haven't learnt
15 Have - taught - have - taught - started - have taught
16 saw - haven't seen
17 Have - ever won - won
18 has worked
19 haven't lived
20 was - wanted
11 joined - was
12 has painted
13 discovered
14 have studied - haven't learnt
15 Have - taught - have - taught - started - have taught
16 saw - haven't seen
17 Have - ever won - won
18 has worked
19 haven't lived
20 was - wanted