They are making too much noise here. Let

对医院来讲，在输血前没有必要检验，患者是否患有某些疾病，包括潜伏期。（）

英译汉。

1. My favorite teacher is our English teacher. She is about thirty years old. She is thin and isn't tall. 2. She

 likes reading books very much. And she also likes music. She is good with students. She is strict with us, 

 but she is kind to us, too. Her classes are interesting. She often tells us stories in English. So all the

 students in our class like her very much.

1. _____________________________________。

2. _____________________________________。

接近信号机以显示（）为定位。

A、绿色灯光

B、注意信号

C、停车信号

D、进行信号

对于"大众传播"的描述，正确的是（）

A.是最基本的传播形式

B.是建立人际关系的基础

C.是非组织群体的传播活动

D.以职业性传播机构为传播者

E.是组织以外群体的传播活动

生态系统的结构主要指它的（）和（）。