51. When carbon is added to iron in proper ______the result is steel.

A) rates            B) thicknesses       C) proportions               D) densities

 52. You should try to ______ your ambition and be more realistic.

A) reserve          B) restrain          C) retain                    D) replace

 53. Nancy is only a sort of ______ of her husband’s opinion and has no ideas of her own.

A) sample          B) reproduction      C) shadow                  D) echo

 54. Now that spring is here, you can ______ these fur coats till you need them again next winter.

A) put over         B) put away         C) put off                   D) put down

 55. There is a _____ of impatience in the tone of his voice.

A) hint             B) notion           C) dot                      D) phrase

51.C) proportions  52.B) restrain   53.D) echo     54.B) put away       55.A) hint