单词拼写。
根据下列句子及所给汉语注释，写出空缺处各单词的正确形式，每空只写一词。
1. The exercises are designed to ________ (增强) your stomach muscle.
2. Don't be frightened by the television camera. Just speak (自然地).
3. The boy spoke in a low voice (承认)that it was his fault.
4. Are you well __________(准备) for the entrance examination?
5. As the storm drew near, black clouds were __________ (聚集) over the sky.
6. However, his __________ (知识) of French remained very weak.
7. (令人吃惊的是) , some graduates with qualification failed to find jobs.
8. The Bank of China has a lot of __________ (支行) in the world.
9. This kind of tree can only grow in the __________ (北方) parts of China.
10. Nuclear physics is ________(超出) my understanding.