---Tom, why don’t we help our son work on his papers?---We’ve already done more than we ________.He is on his own this time.
---I’m sorry! I would have taken him to hospital if I had known he was seriously ill. --- But ______ .
--- Are you going to see The Flowers of War by Zhang Yimou? --- _______It’s said to be too good a film to miss.
No matter ______ the CRH accident in Wenzhou, it had and will have much warning significance.
It has been announced that all the students ____ put on masks before going to school in case they are infected with SARS virus.
—Have you been to the Great Wall? —Perhaps not in my memory. ________, it might have been during my early childhood.