1 . We were occupied performing domestic chores when ________(interrupt) by a knock on the door. (所给词的适当形式填空)

2 . We could hear the sound of the rain and our footsteps ________ (mix) with our laughter. (所给词的适当形式填空)

3 . Can those _______________ (seat) at the back of the classroom hear me? （所给词的适当形式填空）

4 . They are in favor of reforms__________(demand)by people all over the world. (所给词的适当形式填空)

5 . The professor suggested the problem __________(refer) to be solved at once. (所给词的适当形式填空)

6 . After washing, we wandered around outside the tents drying in the sun and getting________(dress). (所给词的适当形式填空)

7 . I saw her sitting at a window table, __________(bathe) in sunlight. (所给词的适当形式填空)

8 . With all the books he was interested in ________ (buy), Tom left the bookshop with great satisfaction.(所给词的适当形式填空)

9 . Foods ________ (intend) for old people and children should be soft, tasty, small and light. （所给词的适当形式填空）

10 . David is lively and cheerful while his sister Catherine is quiet to shyness, never speaking unless ________ (speak) to.