What should you do _when___greeting someone for the first time in_英语解答

What should you do _when___greeting someone for the first time in Germany?
我在网上查到原句 when you greet someone .省略不是be 动词时吗?这个也不是when you are greeting someone. 翻译也不通啊?正在打招呼也不对啊?when you greet someone 怎么省略成_when___greeting someone ?答案填的是这个,如何解释?很急!谢谢!

人气：121 ℃　时间：2019-08-21 08:52:55

解答

横杠是怎么回事?
如果答案是“when greeting someone”那就好办了.
这是因为省略,本应为“when greet some one”,但动词不能作主语,而且这里既不能用祈使句,也不表被动,所以只能是现在分词.
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