女性，45岁，间歇性发作咽下困难3个月，伴反酸烧心，可因情绪波动诱发。食管造影未见异

— Look, that’s Tom—the lost boy!

— It’s really_______great comfort to see him safe again. He is sure to bring_______comfort to his worried mother.

A．a; a

B．the; the

C．a; /

D．the; /

句型转换

1. Mr Hu taught her math last year.(改为一般疑问句)

    _____ Mr Hu _____ her math last year?

2. His friend took the photos yesterday.(改为否定句)

    His friend _____ _____ the photos yesterday.

3. Tom often goes skating on Sundays in winter.(改为一般疑问句)

    _____ Tom often _____ skating on Sundays in winter?

4. She doesn't wash her clothes on Sundays.(用last Sunday代替on Sunday并改写句子)

    She _____ _____ her clothes last Sunday.

5. Were there any actors at the theater? (作否定回答)

    No, _____.

括号内是区别下列各组物质的方法，其中错误的是（　　）

A．硫酸铜固体与硝酸钾固体（蒸馏水）

B．空气与氧气（带火星的木条）

C．食盐水与蒸馏水（蒸发）

D．氢氧化钙溶液和氢氧化钠溶液（石蕊试液）

机组大修时，汽轮机的化学检查部位及内容是什么？

国际交往中，并排站立、行走或就座时，为表示礼貌，主人理应主动居右，而请客人居左；男士应主动居右，而请女士居左。