Question

Pieces of bamboo or wood ________ books between 2^nd and 5^th century AD.
A. used to formed       B. used to form
C. were used to form    D. used to beforming

Answer 1

C

试题分析：句意：竹片或木片被用来制成书在公元2-5世纪。这里是短语be used to do被用来;used to do过去常常;根据句意故选C。
点评：本题难度适中。固定短语主要考查它们的意义，但是它们是在一定的语言环境下而出现的，所以考生必须能正确理解句子的句意。这里主要区别含有use的两个固定短语。
即学即练：Jack ________ assist Mary in her lessons.
A. used to assist ed     B. used to assist
C. were used to assist  D. used to assisting
解析：B。句意：杰克过去常常帮助玛丽学习功课。