单词拼写（共5小题；每小题2分，满分10分）
根据句意和首字母或汉语提示，将单词的正确形式完整地写在答题卡相应的位置上。
He took an active part in all kinds of activities, i       tennis, swimming, running and so on.
The little boy o        his seat to an old lady on the crowded bus.
Air pollution is one of the g        problems in the modern world.
Believing in yourself is the first step on the road to           (成功).
It’s nice of you to provide us with the        (有价值的)information.