单词拼写根据所给首字母或汉语写出空缺处单词的适当形式，使句子完整，语法正确，每空一词 (共10小题；每题0.5分，满分5分)
The Great Wall was first c_____ in the north of China over 2,000 years ago.
The main d_____ of the Internet are that it has too much information that has not been evaluated for accuracy and that it is transforming the way people spend their time.
A large number of copies of the novelist’s latest work have been sold as soon as it was published; it is really a b_____ book.
Jim just graduated from college and he was not sure whether he had the q_____ for the job, but he applied for it anyway.
Formal dress is not required at this party — you may come in c_____ clothes.
At the end of the lecture, the whole audience _____ (鼓掌) the speaker for his wonderful speech.
I think I’d better apologize to him tomorrow for not keeping the _____ (预约).
Two explosions occurred near the Boston Marathon finish line, at least 6 people injured， which was really _____(令人难以置信的).
It is unwise to _____ (牺牲) our environment for more economic profits.
As the first lady, Peng Liyuan made her diplomatic debut (初次露面) with an _____ (优雅的) image that has impressed the public.