if they knew how difficult it was to drill through the hard rock,they would lose heart.这里为什么要加it,其什么作用
问题描述:
if they knew how difficult it was to drill through the hard rock,they would lose heart.这里
为什么要加it,其什么作用
答
how difficult (表语)it(形式主语) was(系动词) to drill through the hard rock(真正主语)
it的存在是为了把真正主语部分放在句末,使句子显得平衡。
答
it是形式主语。
答
形式主语 这里有一个宾语从句how difficult it was to drill through the hard rock 真正的主语是to drill through the hard rock 为了避免头重脚轻 所以用了形式主语it
答
it 是形式主语,指代它后面的动词不定式,正常语序为:to drill through the hard rock is difficult,是由how引起的宾语俗语,在这里,作为if they knew 的宾语,语意为:如果他们知道钻透这块坚硬的岩石是多么的困难的话,他们将去失去信心。