2.If we aren't sick, we_____ (could ,should ,have to) go to school.
3.Human beings ______ (could ,should ,must) eat and drink to live.
4. If you're sick, you______ (could ,should ,must) go to see a doctor.
5.To get to Kowloon from Hong Kong you____(have to,could,should either take the M.T.R. or a bus. They are equally fast.
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6.We_____(must,could,should)go to Temple Street market or find a shopping centre. Either place is a good choice. 7.But if you want to buy something cheap we_____(should,could,must)go to the market.
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8. I start school at 9 am, I don't want to be late so I______(should,could,have to)catch the bus before 8:30.