A
2My friend who wants to become a psychologist loves helping people.
3This is the book that our teacher was talking about.
4Many experts will attend the conference where new theories will be presented.
5Our neighbour whose daughter lives in Portsmouth is going to the UK soon.
b
2What makes him seem friendly is that he's always singing.
3What you should remember is that no one is perfect.
4What I find really annoying is that Paul always interrupts when I speak.
5What I'll never forget is that she gave me a really nice smile.
c
2Try phoning...
3We stopped having...
4I tried apologising
5You must remember(к глаголу, который закрыт пальцем, добавить окончание"-ing".)