Environmental concerns served as one of the main reasons for the change, Chen was quoted as saying.http://www.chinadaily.com.cn/china/2006-09/26/content_697002.htm
參考答案:serve as:
vt. 担任(充当,起...的作用)
例句与用法:
1. In a way, I'm glad you made that mistake, for it will serve as warning to you.
在某种意义上来说，你犯那个错误我倒很高兴，因为那个错误会对你起警告作用。
2. These philosophical views serve as a guide in life.
这些哲学观点可以作为处世指南。
3. Let this be an example (ie May this punishment serve as a warning) to you.
你要以此为鉴戒.
4. The episode could reasonably serve as a unique epic of royal espionage!
这一事件理所当然地堪称是国王间谍活动的的独一无二的史诗。
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