风门分()和(),燃气时多用()
参考答案:一次风门;二次风门;一次风门
下列不属于短期政府债券的特征的是( )。
A.交易成本高
B.流动性强
C.违约风险小
D.收入免税
I’ve _______ to swim last week. But unfortunately I had a bad cold and therefore couldn’t go.
A.refused
B.saved
C.intended
D.managed