发生 * * 皲裂的常见原因是
A．催乳激素B．催产素C．哺乳方法不当D．让新生儿早吸吮多吸吮母乳E．喂乳前消毒 * *
参考答案：C
在探索遗传物质的过程中，赫尔希和蔡斯做了T2噬菌体侵染细菌的实验。下列有关叙述正确的是[ ]
A．用32P、35S标记同一组T2噬菌体的DNA和蛋白质
B．该实验的步骤是标记、培养、搅拌、离心、检测
C．用含有充足有机物的完全培养基培养T2噬菌体
D．该实验证明了DNA是主要的遗传物质
根据句意，用括号内所给单词的适当形式填空。
1. — Would you like to play computer games with us?
—Yes, with (please).
2. — Could you (fetch) me some hot water, dear?
—Sure, Mom.
3. Let's raise money to help the (disable).
4. There are many helpful social (社会的) (organize) in the world.
5. She is blind. That is to say, she is (able) to see.
