Odpowiedź:
1 the most difficult
2 are you waiting
3 isn't a (single) cloud
4 were built
5 times a day
6 went walking
7 could eat
8 better cooks
9 enjoys playing tennis
10 was directed
11 has already bought
12 of your wife's hair
13 were having a nap
14 doesn't start studying
15 on Monday evening
16 were fifteen guests
17 going to a concert
18 don't be late
19 are you interested in
20 more comfortable than going