aim at
aim at
China has carried out some new agricultural policies,aiming at raising farmers’ living standards.中国已执行了一些新的农业政策,旨在提高农民生活水平.
aiming at raising .这个分词短语在句中做什么成分?
为什么不用aimed at
China has long been a leader in the field of genetic research aimed at improving agriculture.
这里为什么不用aiming?
赞同xxtygyb的,
第一句,aiming at以现在分词形式,修饰前面整个句子.中国已执行了一些新的农业政策,（这个动作）旨在提高农民生活水平.
如果这里改成China has carried out some new agricultural policies aimed at raising farmers’ living standards.这样的话,便是过去分词修饰polocies了,中国已执行了一些新的农业政策,（这个政策）旨在提高农民生活水平.也不是不能用,只是意思变了.
第二句,aimed at,aimed 以过去分词形式,修饰前面一个词.China has long been a leader in the field of genetic research aimed at improving agriculture.这句话的意思是中国在遗传研究领域已经是个佼佼者,这个研究旨在改善农业,如果用aiming at那么便是修饰China has long been a leader in the field of genetic research 整句话,这是讲不通的.