29. We wear dark glasses in order to ____________ our eyes ____________(保护……使……免受……) the strong sunlight.

28. People from the two countries have no difficulty _____________ (understand) each other.　

27. How much does that garage business __________(收入，进帐) each month?

26. The ___________(大多数)of Americans enjoy traveling from place to place.

25. I have already had such a stamp, so I ___________(交换) the extra one for a new stamp.

24. _____________(不要拘束), Jones, and help yourself to the food you like.

23. He can be very rude sometimes, but ___________, I still love him.

22. ________(大量) of people in China are learning English as a second language.

21. The party ____________(以……结束) an old folk song.

20. You should work tonight ____________ watching TV.