操作系统的作用是( )。A．把源程序编译为目标程序 B．实现硬件的转接 C．便于进行

阅读理解。

     Last week my youngest son and I visited my father at his new home in Tucson, Arizona. He moved there

a few years ago, and I was eager to see his new place and meet his friends.

     My earliest memories of my father are of a tall, handsome, successful man devoted to his work and family,

but uncomfortable with his children. As a child I loved him; as a school girl and young adult I feared him and

felt bitter about him. He seemed unhappy with me unless I got straight A's and unhappy with my boyfriends if

their fathers were not as "successful" as he was. Whenever I went out with him on weekends, I used to

struggle to think up things to say, feeling on guard.

     On the first day of my visit, we went out with one of my father's friends for lunch at an outdoor café. We

walked along that afternoon, did some shopping, ate on the street table, and laughed over my son's funny facial

expressions. Gone was my father's critical air and strict rules. Who was this person I knew as my father, who

seemed so friendly and interesting to be around? What had held him back before?

     The next day my dad pulled out his childhood pictures and told me quite a few stories about his own

childhood. Although our times together became easier over the years, I never felt closer to him at that moment.

After so many years, I'm at last seeing another side of my father. And in doing so, I'm delighted with my new

friend. My dad, in his new home in Arizona, is back to me from where he was.

1. Why did the author feel bitter about her father when she was a young adult? [ ]

A. He was silent most of the time.

B. He was too proud of himself.

C. He did not love his children.

D. He expected too much of her.

2. What does the author think of her father after her visit to Tucson? [ ]

A. More critical.

B. More talkative.

C. Gentle and friendly.

D. Strict and hard-working.

3. The underlined words "my new friend" in the last paragraph refer to _____. [ ]

A. the author's son

B. the author's father

C. the friend of the author's father

D. the café bar

螺纹标注中，如果是左旋螺纹，应（）注明旋向。

A.省略

B.用RH

C.用LH

D.用L

细胞膜内外正常Na⁺和K⁺浓度差的形成和维持是由于

A．膜上Na⁺-K⁺泵的作用
B．膜在安静时对Na⁺通透性大
C．Na⁺、K⁺易化扩散的结果
D．膜在安静时对K⁺通透性大

肝阳上亢所致头晕多表现为

A．头晕头痛，痛有定处
B．头晕胀痛，头重脚轻
C．头晕面白，神疲体倦
D．头晕且重，如物裹缠

下列各项属于企业领导培训内容的有( )。

A．职业道德

B．知识产权法规

C．经济政策

D．法律法规

E．外贸知识