3. Yesterday they heard a strange noise and at each other in horror.
a) looked
b) were looking
c) had been looking
d) had looked
4. A group of scientists are travelling around Africa. How many countries so far, I wonder?
a) have they been visiting
b) have they visited
c) they have visited
d) do they visit
5. I the dishes before I went for a walk with my friends.
a) washed
b) had washed
c) had been washing