Put «to» where necessary:
1. I’ll have (hurry). 2. You ought (take) a holiday. 3. You must (look)
both ways before crossing the road. 4. You are (go) at once. 5. He used
(spend) a lot of time in the library. 6. You may (keep) my book for a week.
7. We had (wait) as the manager was out. 8. Should I (tell) him the truth?
9. You needn’t (turn on) the light. I can (see) quite well. 10. I knew the town
so I was able (advise) him where to go.