Seated on the grass ,the girl felt happy的问题这里是主动的关系,为什么不用Seating?

Seated on the grass ,the girl felt happy的问题这里是主动的关系,为什么不用Seating? sheep f____ on the grass . in the grass on the grass怎么区分? 草丛里有条蛇是on the grass还是in the grass? Sit on the grass.还是 Sit in the grass? in the grass 与on the grass的区别 the sign on the grass是什么意思 we found the two children seated on the floor------为什么用seated 而不用seating? don't walk on the grass=? on the grass 用中文怎么说 What can you see on the grass? Don't_____（践踏）on the grass. walk on the grass的意思 Peter,__________(not walk) on the grass. in the snow还是on the snow,in the grass还是on the grass hould walk on the grass.（改为否定句) You_____ _____ walk on the grass. Don't walk on the grass 改为同义句---walk on the grass Don't walk on the grass.You ____ _____walk on the grass