英语翻译
变否定：
1I'm pumping up this tyre
2he's playing hopscotch with the girls
3they're eating standing beside a lake
4the children are enjoying billy's birthday parte
变一般疑问;
1NOW THE DOG IS HOLDING THE STICK BETWEEN ITS TEETH
2she's coming out of that shop
3they 're eating sandwiches cakes and biscuits