Here are the completed sentences with the correct verb forms:

1. I enjoy **playing**.
2. Let's hurry! We must **finish** (paint) the office before 3:00 today.
3. As we don't agree to **carry out** a proposal we generally avoid (discuss) the subject.
4. I don't mind **reminding** you to (lock) the door, but you'd better **try** (remember) on your own.
5. Please step **in** (interrupt) when I'm explaining something to you.
6. You can **ask** questions at the end.
7. He admitted **entering** the house but refused (steal) the money.
8. I don't really fancy **spending** my whole holiday with your cousins.
9. I'd rather **spend** my time with you.
10. We had hoped **to finish** the project by the end of the month but we keep (delay) by changes in the plans.
11. You'd better **go** and see the boss and say what you’ve done.
12. If you put off **explaining** it to her, she’ll only be more annoyed.
13. Those shirts need **ironing**, but you don't need **to iron** them now.
14. Are we permitted **to bring** guests to the ceremony? I’d like **to invite** my friends.

Feel free to ask if you need any further assistance!