We watched the ship...slowly over the horizon.
a)disappear b)to disappear
c)being disappeared d)to disappearing

a) disappear

Объяснение:

Это сложное дополнение (Complex Object). Поскольку глагол watch относится к группе глаголов восприятия, после него в этой конструкции используется инфинитив без частицы to:

watch smb/smth do

То есть предложение должно выглядеть так:

We watched the ship disappear slowly over the horizon.

1. isn't she

2. aren't they

3. can't they

4. can't he

5. aren't they

6. has she

7. haven't they

8. can they

9. is he

1d

2b

3a

4b

5с

did he?

don't they?

can't they?

he?

we?

my friend can play computer games, can't he?

group of russian students will visit great britain in april, won't they?

we went to the park yestaerday, didn't we?

our head teacher answers for educational programm, doesn't he?

i am going to the cinema