Some walls have been knoched down and some houses pull down.among the sentence "some houses pull down",is this language structure correct?
热心网友
语法不对。前面是have been knoched down ，后面如果是省略，要用pulled down.如果是现在时，pull down不符情况。如果是pulled down就对了。
热心网友
"some houses pull down"是对的，这是some houses have been pull down 的省略，因为句子前面已有some walls have been knocked down的相同结构，所以可承前省略
热心网友
"some houses pull down" = "some houses being pull down"因为上半句有用过“have been”，所以作者在下半句省略了再次用“be”，以求简洁。