Question

英语语法问题？

He found it a lot harder to concentrate on drills that afternoon and when he left the building at five o'clock,
如果It是宾语代表谁啊
a lot harder to concentrate是从句么，为什么还用不定式啊，harder也不是名词啊
感觉这句看不出来宾语，
it header to concentrat做宾语也看不到it代表谁啊

Answer 1

He found it a lot harder to concentrate on drills that afternoon and when he left the building at five o’clock.
先看这句话的意思：
他发现那天下午很难将精力集中在训练上， 而且他在5点钟就离开了大楼。
1）it 形式宾语，代表： to concentrate on drills。
2） a lot harder to concentrate on drills 作it的宾补, 不是从句。