7 Fill in the gaps with must, mustn't or needn't. 1 You........................shout in the library. 2 You........ - I have some. go to the post office to buy stamps 3 You........................ smoke in this building. 4 She I fill in this application form if she wants to apply for the job. 5 You........................drive to the party as Kate can take you in her car. 6 You............. swim in the sea as the water is polluted. ​