39.A.teacher

B.student

C.friend

D.parent

40.A.before

B.enough

C.now

D.yet

41.A.pictures

B.covers

C.pages

D.knowledge

42.A.business

Bhomwork

C.shopping

D.reading

43.A.failed

B.enjoyed

C.decided

D.needed

44.A.study

B.work

C.travel

D.wait

45.A.learn

B.finish

C.worry

D.use

46.A.so

B.But

C.Or

D.And

47.A.if

B.befor

C.until

D.even

48.A.stay

B.stat

C.stop

D.spend

49.A.free

B.slow

C.ready

D.polite

50.A.language

B.way

C.life

D.story