1 . 当你网购时，在保证安全方面你有其他好的建议吗？（省略句）
________________________________________________________________________________

2 . The response from a publisher comes back and the writer eagerly opens and reads it, __________ (他们的心沉了下来) when they reach that final sentence.   (根据汉语提示填空)

3 . 感到既尴尬又惭愧，我干任何事情都不能集中精力，然后我决定跟父母说实话。(汉译英）

4 . 3个小时过去了，他变得越来越紧张。
Three hours ________________________, he became more and more nervous.

5 . ___________ the 18th century, Peking Opera has over two hundred years of history.
京剧的起源可以追溯到18世纪，距今已有两百多年历史。