10元的25是______元，20米的34是______米，______吨是40

腮腺导管开口于

A．舌系带

B．舌下阜

C．颊黏膜

D．舌扁桃体

E．上颌第二磨牙的颊黏膜处

指出错误并改正。

1. My friend said his sister had been there a week ago.

    ____________________________________

2. Zhang Jun said that he had joined the League in August 2006.

    ____________________________________

3. He asked his sister if she is interested in the performance.

    ____________________________________

4. My head teacher asked me why had I been late that day.

    ___________________________________

5. She said she would go to New York next day.

    ___________________________________

两个完全一样的直角三角形拼成的图形不可能是（　　）

A．长方形

B．平行四边形

C．等腰三角形

D．直角梯形

科学家最近研制出可望成为高效火箭推进剂的N(NO₂)₃（如下图所示）。已知该分子中N-N-N键角都是108.1°，下列有关N(NO₂)₃的说法正确的是

A.分子中N、O间形成的共价键是非极性键

B.分子中四个氮原子共平面

C.该物质既有氧化性又有还原性

D.15.2g该物资含有6.02×10²²个原子

患者女，47岁，左眼球向外下突出2月余，逐渐加重，伴复视，CT示左侧额窦扩大，窦腔内呈软组织密度，骨壁变薄，左眼球受压移位，诊断为（）

A.额窦癌

B.额窦粘膜下囊肿

C.额窦粘液囊肿

D.额窦骨纤维异常增殖症

E.慢性额窦炎