是in chair还是on chair

是in chair还是on chair 是sit on the chair还是sit in the chair 是sit in a chair还是sit on a chair? sit in a chair还是sit on a chair? 是sit in a chair还是at a chair on the chira和in the chair的区别在椅子上是用ON THE CHAIR 还是 IN THE CHAIR? 坐在椅子上用sit on the chair 还是sit in the chair 坐在椅子上是 sitting on a chair / sitting in a chair / sitting down a chair哪些是对的? 做在椅子上是 还sit on the chair 还是sit on the chair 在椅子上是in the chair还是on the chair?为什么?为什么在公交车上是用on而在车里用in? chair is comfortable to sit on 还是in ? in the chair 和 on the chair的区别 求坐在椅子上的英语?是sit in chair还是sit on chair?那说坐在或躺在床上的呢？ is.it.book.on.the.Chair.还是is.the.Book.On the chair对 The bag is ___ the chair.横线填in还是on? on my chair sit on the chairon the chair 是状语还是宾语sit是及物动词还是不及物动词? on the sofa还是in the sofa on the bed还是in the bed on the chair还是in the chairon the sofa还是in the sofa on the bed还是in the bed on the chair还是in the chair?急!~~~在什么情况下用in什么情况下用on呢?请高人指点啊··