(2010·辽宁高考)Doctors say that exercise is important for health, but it ________ be regular exercise.

ionally, Chinese people _____ the Chinesecharacters Double Happiness and stick them onto walls or doors for weddings.

don’t know how it ___________ that our car was bumped from behind.

Where _______ you put my dictionary?— I left it on your desk when you _______ to Tom

To their disappointment，Dr Wang gave a speech about the economy without even a passing________to the problem of unemployment