问题补充：
------ Do you know where Li Ming is working ? ------ Maybe in Guangzhou, I think.
A. at first
B. at least
C. at last
D. at present
答案：
A. at first
B. at least
C. at last
(答案→)D. at present
解析：句意：你知道李明目前在哪工作吗?我想可能在广州。A. at first 首先； B. at least至少；C. at last最后，最终； D. at present现在，目前。根据句意，问句又是现在进行时，故选D。
