I didn't know how long____ such aA.has he had B.he has caught C.he had had D.had he caught

I didn't know how long____ such aA.has he had B.he has caught C.he had had D.had he caught
I didn't know how long____ such a
A.has he had B.he has caught C.he had had D.had he caught

I didn't know how long____ such aA.has he had B.he has caught C.he had had D.had he caught
C 这个句子主句有didn't 所以从句也要过去式
A B 都是现在完成时 不是过去 排除
主从复合句中 从句按陈述句语序 所以选C
D是疑问句语序

C. he had had

C

C 此句是宾语从句，主句是一般过去时，从句也要相应的用过去的某种时态。此句是how long 引导的宾语从句，从句要用陈述句语序。所以D不对，语序不对