Question

 (2011年陕西宝鸡检测)Mary，I should tell you it is the third time that you________.

A．forgot to do                         B．forgot doing

C．have forgotten to do             D．had forgotten doing

Answer 1

解析：选C。考查时态和非谓语动词。“It is(was)the＋序数词＋time＋that从句”，表示“是某人第几次做某事”。在此句型中，若前面为it is，则that从句用现在完成时；若前面为it was，则that从句用过去完成时。而forget to do sth.表示忘了应去做某事，forget doing sth.表示忘了已做过某事。根据语意可知此题应选C。