68. Do you know the --------- (high) of this tall building?

68。Do you know the (height,名词,高度) of this tall building?你知道这座山的高度是多少吗?这里需要填形容词high的名词形式,来当动词know的宾语。67。Trees are the best (fighters,名词,战士) against air pollution。树木是抵抗空气污染的最好战士。这里也要填名词,是拟人的用法。61。My teacher always answers my questions (patiently,耐心地,副词)。我的老师总是很耐心地回答我的问题。这里要填副词形式,因为它修饰的是动词answer。