“黄变米”中含有____ ，能够导致中毒，和肝癌．

写几句保护地球的标语。

如：精心保护地球，造福子孙后代。

Dear Sandy,

    I am very glad to enter my school. I enjoy the life here except for the school lunch. I prefer hamburgers,ice creams and potato chips,but we are not allowed to order them according to the school rules. I usually have little for lunch and I often feel tired and can't follow the teachers in the afternoon classes. What should I do? Do you have any good ideas? Please write to me as soon as possible.

Yours sincerely,

Lucy

注意事项:1）词数90左右，开头和结尾已经写好，不计入总词数;

2）文中不得提及真实的人名、校名等相关信息。

Dear Lucy,

    I am glad to receive your letter.

Yours,

Sandy

关于内能下面说法正确的是（）