鹅口疮好发于（）
A.新生儿
B.婴儿
C.学龄前儿童
D.学龄儿童
E.青春期儿童
参考答案：A
Her new book is about a murder mystery ________ on actual murders that took place in Florida several years ago.
A．having been based
B．to be based
C．based
D．having based
市场体系的三大支柱是( )。
A．商品市场、技术和信息市场、房地产市场B．商品市场、资本市场、劳动力市场C．商品市场、技术和信息市场、劳动力市场D．生产资料市场、期货市场、技术和信息市场
