Children,if growing up in a multicultural society,are more likely to embrace diffenrent cultures and values.为什么不能用grow呢？
(如果不是省略形势，就一定是children are growing。。。吗）状语从句同时具备下列两个条件才能省略吗:主句和从句的主语一致，或从句主语为it；从句主要动词是be的某种形式。从句中的主语和be动词常可省略。没有第二条行不行，为什么
条件和时间状语从句在书面语言中往往可以把从句中的主谓部份改为分词短语作状语。这种情况貌似省略了从句中的主语以及某些没有必要出现的助动词（进行时态助词或被动助动be）。
1、如果分词的逻辑主语是句子的主语，用现在分词，如：
Children, if (growing) up in a multicultural society, are more likely to embrace different cultures and values.
= Children, if (they grow) up in a multicultural society, are more likely to embrace different cultures and values. (they 指代children)
When (coming), he will join us in the activity.
= When (he comes), he will join us in the activity.
2、如果句子的主语是分词的逻辑宾语，则用过去分词，如
If (invited) to the party, he will sing us some songs.
= If (he is invited) to the party, he will sing us some songs.
After (appointed) to the post, he began to fulfill his obligations.
= After (he was appointed( to the post, he began to fulfill his obligations.
3、如果分词的逻辑主语为与主句主语不一致，这个分词必须保留自己的逻辑主语，如：
If (the film interesting), I am sure to see it.
= If (the film is interesting), I am sure to see it.
When new year approaching, they always get ready for it ahead of schedule.
= When new year is approaching, they always get ready for it ahead of schedule.
If time permitting, we could do it better.
= If time permitted, we could do it better.
if student pay full fees，it will raise enough finance for university。可不可以省略成，student，if paying full fees，will raise enough finance for university
追答可以，if paying full fees 变成了插入性状语。原来的语气是强调条件，插入中间变成了捎带提及。改写后，分词状语的逻辑主语与句子主语一致。
追问虚拟语气的条件状语从句，可不可以怎么省略成短语
追答只要主句中用了虚拟语气，从句也可以这样改写。但是要注意分词的时态形式，对现在或将来虚拟用 doing 或 done，对过去虚拟用 having done 或 having been doing
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