Question

【题目】David and Tom are good friends. They ______ each other for ten years.

A. knew B. know C. have known D. had known

Answer 1

【答案】C

【解析】

试题分析：句意：大卫和汤姆是好朋友。他们已经认识10年了。结合句意可知，是说明他们现在的情况，也就是到现在为止，他们已经认识10年了，故时态运用现在完成时态，答案为C。