Question

la actividad es cambiar el verbo a la forma correcta en Present Perfect

Answer 1

1.have improved
2.has became
3.have invented
4.have caused
5.have learnt
6.have done
7.has found
8.have consulted
9.have met
10.have doubled
11.has been
12.have been
13.has hated
14.have been
15.have liked