俄罗斯的乌拉尔山区为世界重要的金属矿产地（铜、铁、铝土、锰等），炼铝工业为了降低

化学与能源、环境关系密切，请用学过的化学知识回答下列问题：

（1）化石燃料燃烧会产生的大量排放引起的环境问题是 _________ ．

（2）煤的气化是高效、清洁利用煤的重要途径，其过程是可将煤炼成焦炭，再将焦炭在高温下与水蒸气反应，得到一氧化碳和氢气．该反应的化学方程式是 _________ ，该反应所属的基本反应类型是 _____ ．

用所给单词的适当形式填空。

1. Thanks a lot for______(give) me the book.

2. —Thank you for_______me to your party. But I call't accept (接受) your_______because

I have a lot of work to do.

    —That's a11 right. I also______Lin Tao and Jim to come. (invite)

3. Jim______(beginn)______(learn) Chinese two years ago.

4. The old man asked the policeman______(help) him.

5. We______(get) ready for a party now.

6. He is a______(luck) boy.

7. Thank you for______(help) me.

8. There are two basketball______(match) tonight.

9. Do you know that girl? She comes from an______(America) city.

10. He often goes______(fish) in the park.

原始大气中不含有（　　）

A．游离氧

B．氨

C．甲烷

D．水蒸气

预防性树脂充填类型B使用的充填材料是

A．不含填料的窝沟封闭剂
B．含填料的窝沟封闭剂
C．玻璃离子水门汀
D．流动树脂
E．后牙复合树脂

清管作业打开盲板前应注意什么？