4. Put the verbs in brackets in correct form using Conditional 2.
1. She (understand) everything, if you (explain) it to her.
2. What you (do) if there (be) a fi re in the building?
3. Where you (to go) if you (visit) London?
4. We (stay) at the hotel if it (not to cost) so much money.
5. If you (invite) Bill, we (have) to invite his friends, too.