It ________ nearly two weeks ______ I had received his letter.
--- Shall we go for a drink at one o’clock this afternoon? --- . Will two o’clock be OK?
Scientists study ____ human brains work to make computers.
The notice came around two in the afternoon____the meeting would be postponed.(2012•江苏)
____medicine works in a human body is a question ____ not everyone can understand fully.
The media today can draw government’s attention to ____help is really needed.