cross和across有什么区别（When is the road is clear,it is safe to---

cross和across有什么区别（When is the road is clear,it is safe to--- if the road is___,it is safe to cross 为什么空里是填clear而不是empty? when it is safe （） the road if you are sure that the road is clear ,it is always safe to if you are sure that the road is c____,it is safe to cross t Dog tell the blind person when it is ---- to cross the road. It is near,just go（）the road.括号里填cross还 across?为什么? what is the safe way to cross the ______ ( not cross ) the road when the light is red 87 ___(cross) the road when the light is green 改错：We must not to cross the road when the light is red. It is not safe to travel by standing at the road hoping to b