before后可接过去分词吗

before后可接过去分词吗　　

有朋友在“答疑中心”问：before后是否可以接过去分词。问题见：　　

现由本站特约作者龙楠老师回答如下：　　

您的理解是对的，Mr. Smith can buy a small present before invited to a party.这个句子有错误，因为before后不能直接跟过去分词，应改为Mr. Smith can buy a small present before being invited to a party. 关于这一问题，《朗文英语语法》明确指出：在after, before, since等之后不能直接跟过去分词，而需用“being+过去分词”。如以下各列均摘自词典：　　

You can’t eat anything before being operated on. 动手术前你不能吃东西。　　

Watkins hit 16 before being bowled by Ambrose. 沃特金斯击球得了16分后被安布罗斯投杀出局。　　

The document was edited before being circulated in its final form. 文件在以定稿形式散发之前经过了编辑。　　

Applicants were required to obtain character references before being considered for the work.  申请工作者必须有品行推荐信才予以考虑。　　

The bill would be submitted for public discussion before being enacted as law. 该法案在获得通过成为法律前，将提请公众讨论。　　

She led for most of the way before being pipped at the post. 她在大部份赛程中都一直领先，但是在终点被超过。　　

The product had not been adequately tested before being put on the market. 这种产品在投放市场前没有进行充分的检验。　　

They stay here a few hours before being sent to refugee camps, which are now almost full.  他们在这儿呆了几个小时后被送往难民营，而那里现在几乎已经满员了。　　

It is normal to spend two or three years working in this country before being posted overseas.  被派往海外之前，通常会在这个国家工作两三年。