这句话里为什么用seated而不用seating?i saw him seated under the tree,thinking.

这句话里为什么用seated而不用seating?i saw him seated under the tree,thinking. we found the two children seated on the floor------为什么用seated 而不用seating? 为什么不用Seating 而用seated呢?有ING的用法吗? he found lucy seated quietly为什么不用Seating 而用seated呢?有ING的用法吗?he found lucy seated quietly Seating herself alone there,she memorized her happy hour.为什么要用seating而不用Having seated或seated? 为什么坐船用by sea不用by the sea Do you know the key to the question?这句话里key后面为什么用to而不用of? I’d like a room whose window looks out over the sea为什么用whose而不用which Not only I but also he is crazy about basketball这句话中为什么要用HE而不用HIM说明一下理由奥.谢里 I found a boy _____at the back of the classroom为什么只能用seated ,而不用siting? I found him seated there,reading.为什么要用seated? Have you seen the TV play?这句话中为什么用see而不用watch? take exercise often,child这句话为什么用take 而不用 taking或者to take I'm stuck in a moment这句话为什么不用I而用I'm呢? 为什么Mount Emei前不用the而黑海the Black Sea要加the? have you go back home这句话对否我在电视里听到这样一句话 不知听错没有have you go back home 如果没听错,为什么用 have 而不用do某人回家买票,售票员说的这句话 什么时候用where而不用that?例如 Last summer he went to the city______he had visited twice.这句话横线上为什么只能填that,而不用where？ 这里为什么用be原形的过去分词,而不用was/werewest American near the sea has always been a bad place for earthquakes. 英语语法,hardly did i think it impossible这句话为什么有did还用think而不用thought,还有it后面为什么不用is,谢谢