2.非谓语动词

1.I got on the bus and found a seat near the back, and then I noticed a man______(sit) at the front.

sitting

2.Simon made a big bamboo box _______ (keep) the little sick bird till it could fly.

to keep

3.______(see) from the tallest building, the whole city looks very beautiful

Seen

Tips:如果不缺谓语，就要根据上下文语境和 意思 确定动词的使用非谓语动词: 1.如果与它的逻辑主语是主动关系: 2.如果与它的逻辑主语是被动关系: 3.如果表示将来或目的:

一般用V-ing形式

一般用V-ed形式

一般用动词不定式。