①Look out! You mustn't cross the street now. You must wait for the green light.

当心！你现在禁止过马路。你必须等待绿灯。

②You mustn't spit on the ground.

你禁止随地吐痰。

③You mustn't litter.

你禁止乱丢杂物。

④You must keep off the grass.

你不要进入草地。

⑤You mustn' t pick the flowers.

你禁止摘花。

⑥You must take good care of young children.

你必须照看好儿童。