12. If we don't hurry up, we will be late for the meeting.
13. If we go on wasting electricity, we'll have no fuels to use.
14. If you don't be careful, you will break the glass.
15. If you don't pay attention to the lesson, you won't understand it.
16. In case it rain, you should bring along a raincoat.
17. If we working hard, we will be success.
18. If she taking a shower instead of a bath, she can save water.
19. If you take exercise regularly, you will get fit.
20. If you staying up late, you will be tired.