Viết câu điều kiện

VI, Viết câu điều kiện.
1. Eric can win the race because he trains harder.
If
2. Because Tommy gets bad marks, his father doesn't let him go to the party.
If
3. The actress did not sign the contract, so we couldn't start the movie.
If
4. Mr Potter doesn't publish the novel because it is not interesting enough.
If
5. Helen has breakfast with us because she gets up early.
If