1.When it snows,all streets freeze whith ice.
2.We should stop them from making noise in public places.
3.They did their best to prevent the disruption of the environment.
4.A thirteen-year-old boy is seriously hurt in the traffic accident.
5.My friend and I were on our way to the natatorium then.
6.Is he always late for the meeting?
7.The accident took place at half past two a.m.