Ответ:

1. ... started shouting at the waiter, which upset everyone in the room.

2...., who is the owner of this big garden,

employs three gardeners to look after

the roses

3. Let's go to Weston Park, where we'll be able to have a picnic tomorrow

4. Sandra, whose mother works for the WWF, has lived in many countries, in Africa

5. Matt is afraid of water, whichmexplains why he can't swim