People in the west make ____ a rule to buy Christmas presents for their relatives and friends.
— David has been in high spirits these days? — ______ He should win the first prize in the composition test.
--- What does Maggie look like? --- _________
Jack reached the company out of breath, only _______ he was fired.
ThereareseveralresearchcentersinChina________acertaindiseasecalledBirdFluis beingstudied.
I ___ the French written papers but failed in the English oral examination.