银行汇票的实际结算金额不得更改，更改实际结算金额的银行汇票无效。

— The little girl _____ her seat to the old man on the crowded bus.

—What a kind girl![ ]  

A. took

B. brought        

C. borrowed

D. offered

下列变化不属于化学变化的是（　　）

A．用稀硫酸除铁锈

B．海水晒盐

C．体内葡萄糖氧化

D．食物变馊

属于ANP_A受体的药物是（）

A.山帕曲拉

B.齐留通

C.奈西立肽

D.波生坦

E.阿瑞匹坦

— _____?

— He is a computer engineer. [ ]

A. What does your father do

B. How old is your father

C. What does your father look like

D. How does your father go to work

左心衰竭发生呼吸困难最主要的原因是 ( )

A．肺淤血
B．血氧含量减少
C．肺泡张力增加
D．左心房压力增加
E．肺循环压力增加