at present technology is developing fast that tall building is being pulled down

问题描述:

at present technology is developing fast that tall building is being pulled down
为什么加ing啊,而不是用ed 不是被动关系吗
第二个能不能直接is pulling down啊being在这是啥用法啊.

develop 这个单词没有被动形式,没有被发展这个说法,所以不可以用ed
is being pulled down 是现在进行时的被动语态 be + being+过去分词,你可以写成 is pulled down 但不可以写成being pulled down