-------on the grass,a group of students listeed to stories.应该用sit 还是seat,要用Be+动词ing形式吗?

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 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 you shouldn't walk on the grass(改为祈使句）please ( ) ( )on the grass Please don't walk on the grass.(改为同义句)Please ______ ________ on the grass.