Нет, все верно
............................
1. Have already left
2. Have not seen
3. Has she ever been
4. Have you had
1. To ride a bike
2. To play the piano
3. Skating
4. To draw
5. To play sport
6. Rolleblading
1 is
5 is
6 are
7 am
8 is
9 are
10 is
11 are
12 is ; are
14 is
15 is
16 is
17 are
18 is
19 are
20 am ; are
Нет, просто 30 детей не обязательно есть.