题目

英语翻译
can you tell me how long dinosaurs -------- on the earth before they---------?A had existed ; disappeared B had existed; were disappeared C have existed ; disappeared D have existed ;were disappeared

提问时间：2021-01-17

答案

A 解析：恐龙是史前生物,因此它的存在属于过去完成式,因而需要用had +动词完成时态,即had existed
disappear无被动形态,所以,应该用主动形式disappeared,又因为恐龙灭绝在恐龙活在地球上这一事实之后,所以,前句用过去完成时,后一句用一般过去式,以达到时态对应.
整句话完整翻译：你能告诉我在恐龙灭绝前,它们在地球上存在了多长时间吗?