男性，50岁。咯血200ml后突然窒息，应立即采取的措施是（）

A.输血

B.吸氧

C.去除呼吸道梗阻

D.静滴呼吸兴奋剂

E.推注垂体后叶素

句型转换。

1. I volunteer to clean up the park. My sister volunteers to clean up the park, too. (合并为一句)

        ____ ______  I ______               my sister volunteers to clean up the park.

2.1 would give it to Charities if I won a mill/on dollars. (对画线部分提问)

    ______               you ______ if you won a million dollars?

3. Mike is a ninth grade student. He wants to be a professional singer. (合并为一句)

    Mike is a ninth grade student who                             be a professional singer.

4. He told his teacher about his problems. (改为否定句)

    He                             his teacher about his problems.

5. Become a volunteer today,                             ? (完成反意疑问句)