问题
选择题
Hi, Bill. I _____ you _____ in this city. How long have been here?
A．didn’t know; were
B．don’t kow; are
C．haven’t known; are
D．don’t know; were
答案
答案：A
考查时态。句意：嗨，比尔。我不知道你在这座城市。到这儿多久了？结合语境可知前文无论主从句描述的都是过去动作或状态，故用一般过去式，选A。