1£®Would you care to comment on/upon any troublesome students in your class?

2£®Practising Chinese kungfu can not only build up one's strength, but also develop one's character.

3£®Kitty, take your umbrella. It can keep your skin free from/of being burnt.

4£®She reduced her weight by five kilograms last month.

5£®Her poor English often led to misunderstanding when she first went to England many years ago.

6£®No wonder you are so tired. You have been working (work) all day.

7£®Ted was really confused by the confusing problem which also confused other people for a long time.(confuse)

8£®She looked at her watch and turned regretfully (regret)towards home.

9£®The child slipped and fell, hitting (hit) his head against the door.