什么叫砼外加剂？

He complained that this was the third time he _________ of the changes of the meeting.            

A．is informed

B．was informed

C．has been informed

D．had been informed

根据音标拼写单词，使句子意思完整正确。

1.  He was _____    in Shanghai.

2.  Yao Ming is _____   at playing basketball.

3.  We must study _____  /ha:d/.

4.  It's _____  /kwait/ a nice book. I like it very much.

5.   Tom is a _____     boy, he always says "hello" to his teachers.

生用活血通经，炒炭凉血止血的药是（）。

A.侧柏叶

B.茜草

C.苏木

D.刘寄奴

E.艾叶

下列各组中属于同位素的是(    )。

A．⁴⁰K与⁴⁰Ca

B．³⁵Cl₂和³⁷Cl₂

C．D与T

D．金刚石与石墨

用纸盒包装物品时，盒盖开口过大或是内装物品过重时，应采用（）盒盖形式。

A、双保险式

B、POP式

C、压力式

D、推拉式