Sit ° 为什么他们在名前面加Sit ° 如：Sit °乱伤心 Sit °卡卡 Sit °小树

Sit ° 为什么他们在名前面加Sit ° 如：Sit °乱伤心 Sit °卡卡 Sit °小树 sit sit, sit 为什么sit后有时候加down有时候加on sit in a boat?为什么要加 in呢? The chair is too dirty to sit on.为什么要加on呢?不及物动词在什么时候需要加介词 The seat is warm enough for you to sit.在语法上对吗?sit后面是不是还要加介词? a seat to sit还是sit on如题：an empty seat to 后面加 sit 还是sit on Do sit down是怎么回事为什么前面还有个DO啊,是助动词吗,为什么要加呢?在口语里显的礼貌吗 Only when I saw Tina sit in the dark alone did I realize she was unhappy.did为什么要放在 I 的前面? the chair is comfortable to sit on为什么要加on? There must be a dog sitting behind it .为什么sit 后面加ing if you will sit down quietly,it may alight upon you.为什么要加will? He has got a chair to sit (on),but nobody to talk (to).为什么sit后还得加on?talk （with）不行么? sit up sit 急 sit me