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。
小题1:The exercises are designed to ________ (增强) your stomach muscle.
小题2:Don’t be frightened by the television camera. Just speak        (自然地).
小题3:The boy spoke in a low voice       （承认）that it was his fault.
小题4:Are you well __________(准备) for the entrance examination?
小题5:As the storm drew near, black clouds were __________ (聚集) over the sky.
小题6:However, his __________ (知识) of French remained very weak.
小题7:     (令人吃惊的是) , some graduates with qualification failed to find jobs.
小题8:The Bank of China has a lot of __________ (支行) in the world.
小题9:This kind of tree can only grow in the __________ (北方) parts of China. 
小题10:Nuclear physics is ________（超出） my understanding.