The books you donated are used to children in need.
A. help
B. helped
C. helping
D. helps
网友回答
(答案→)A. help
B. helped
C. helping
D. helps
解析：A 考查used的用法。sth. be used to do sth.=be used for doing sth.“某物被用来做......”；sb. be used to doing sth.“某人习惯于......”；used to do sth.“过去常常做......”。“你捐赠的书被用来帮助有需要的孩子。”故选A。