Выберите правильный вариант модального глагола. Внесите букву, обозначающую правильный вариант ответа:
27. You… walk on the grass!
a) mustn’t b) might c) don’t have to

28. We lost our way again and we… ask a policeman for directions.
a) need b) had to c) must

29. …we leave the room? Is the lesson over?
a) ought b) may c) have to

30. It was very hard work, but we… to do it.
a) might b) had c) should

31. “Liz seems to be avoiding you.” – “I’m not sure, she…have been hurt by my words.”
a) should b) needn’t c) might