Question

13. Was it three years ago _____ these trees were planted? A. when B. since C. that D. in which

Was it three years ago _____ these treeswere planted?
A. when B.since C. that D. in which
答案为什么是C不是B呢？ 请高人解释下 谢谢！

Answer 1

It's ...that...为强调句型，意为；正是/就是...
不能用since.如果用since, ，后面该用these trees had been planted.
相信你能理解和赞同！
祝你不断进步！

Answer 2

强调句型

追问

谢谢，B为什么不对呢？是不是要用完成时啊？

追答

它主要强调那段时间，it is。。that，如果强调完成的话，就不是用was了