根据句意填单词。

1. You should t          notes when having lessons.

2. Reading a           is a good way to practice pronunciation.

3. Mary said m          the words of pop songs helped a lot.

4. Tom likes reading English m          such as Reader Digests and Times.

5. Listening and s          are a little more difficult for Chinese English learners.

6. Don't be afraid to m          mistakes when you practice English.

关于等渗溶液叙述，正确的是（）

A.冰点为-0.52℃的水溶液与红细胞等张

B.溶液的渗透压与冰点之间没有相关性

C.等渗的溶液必然等张

D.0.9%的氯化钠溶液既是等渗溶液，又是等张溶液

E.等渗是一个生物学概念