1.--Must I tell John the news?
--No,you ( ).I've told him already
A.mustn't
B.wouldn't
C.shouldn't
D.needn't
2.The flowers ( ) every day.Or they'll die
A.must water
B.can be watered
C.should water
D.must be watered
要解释
1.D must引起的问句,回答不可用must本身的否定形式,应于needn't或don't have to.2.Dthe flowers指物,所以本句是被动语态。所以排除AC。can表示可以,must表示必须。后半句否则他们将枯萎死掉。must的含义更为合适。此外water本句中词性为动词,翻译为浇水。