Be careful when crossing the road中的cross为什么加ing说清楚原因,

Be careful when you c_______ the street be careful when you corss the m___road Be careful when you walk意思 Be careful when you ____the hill be careful when the floor is wet be careful when you go --------(cross) the road 改错 Do be careful when do your homework You should be careful when you cross the m____ road . Paul,______（be） careful when you cross the road. Please be careful when you go____the road.(cross) Please be careful when you go a( ) the road People need to be careful when they shop online. Be careful when you walk ____ the streetthroughacrossintofrom You must be careful when crossing the street.改为祈使句 翻译 Be careful when you come to the traffic light. 填空题 When you walk___the road,you must be careful. you must be careful when you （ ）the street So we must be careful when we use the Internet.