What substance is ___ to all the students in the class?

为丰富课外活动，提高学生英语口语能力，学生会定于下周六下午举办全校演讲比赛。凡愿参加者可在下周三以前向本班班长报名。有3位外教应邀担任裁判。前10名将获得奖品，以资鼓励。欢迎光临为参赛者加油助威。

We insist that international trade should not be a one-way street.

This corporation is specialized in handing the import and export business of textiles.

I’d appreciate it if you could arrange a visit to the Forbidden City for me.

This experiment resulted in the discovery of a new cure for cancer.

This paper covers the development of the distribution system in the southwest of England from nationalization up to the present time.

因为我们的产品在国内外声誉颇佳，所以产品需求量逐年增加。

我代表本公司请您参加今晚七点的晚宴，希望您能光临。

让我们为远道而来的客人干杯。

他们赞成采取严格的措施来控制污染。