单项填空 1. —write to me when you get home. — . a．i must b．i should c．i will d．i can 2. mr. bush is on time for everything. how it be that he was late for the opening ceremony? a．can b．should c．may d．must 3. —is john coming by train? —he should, but he not. he likes driving his car. a．must b．can c．need d．may 4. —i heard they went skiing in the mountains last winter. —it true because there was little snow there. a．may not be
