工厂必须极其小心地处理有毒化学品。

Factories must handle ___toxic chemicals with extreme care.

切勿吸入塑料燃烧产生的有毒烟雾。

Never breathe in ___toxic fumes from burning plastic.

汽车排放有毒气体，污染我们呼吸的空气。

Cars emit ___toxic gases which pollute the air we breathe.