5. —We won the English speaking contest. —Congratulations! You ___ be very proud of it. A. can B. need C. would D. must 6. She ___ know the answer, but I’m not sure. A. need B. may be C. may D. must 7. That man ___ be our English teacher. Because he has gone to Beijing. A. mustn’t B. shouldn’t C. needn’t D. can’t 8.You ___ swim in this part of the lake. It’s dangerous. A. mustn’t B. needn’t C. may not D. won’t