the chair is soft to ____ 为什么要用SIT ON 不是BE SAT ON

the chair is soft to ____ 为什么要用SIT ON 不是BE SAT ON The chair is comfortable to sit on/还是to be sat on? the chair is very comfortable to sit in 这个地方为什么要用in而不用on the chair is comfortable to sit on为什么要加on? The chair is too dirty to sit on.为什么要加on呢? sit on the chair the chair is too hard to sit on.改为同义句 the chair i Sit on your chair!Now the chair is ______ you. Pam is on the ship.She sit on the chair. A dog is on the chair A.sit B.sitting C.siting D.to sit There is a comfortable chair to sit on .为什么加on The chair is broken,so it is _u________ to sit on