Hello, I you in London. How long have you been here?
A. don’t know; were
B. hadn’t known; are
C. haven’t known; are
D. didn’t know ; were
网友回答
A. don’t know; were
B. hadn’t known; are
C. haven’t known; are
(答案→)D. didn’t know ; were
解析：考查时态。根据句意我现在已经知道你在伦敦了，那么我不知道你在伦敦是过去不知道。所以所以过去时。句意：你好，我不知道你来伦敦了。那么在这里多久了？