39.spare no efforts to do替换try one’s best to do

40.many a 替换many

41.be rushed off one’s feet 替换be busy in doing

42.a handful of替换a little / some

43.meanwhile替换at the same time

44.get to one’s feet替换stand up

45.beneath替换under

46.occasionally替换sometimes /once in while

47.for instance替换for example

48.seldom替换not often

49.wealthy替换 rich

50.amazing替换surprising

51.as a matter of fact 替换in fact