记账式债券因为发行和交易无纸化，所以效率高、成本低且（）。
A.流动性高
B.交易安全
C.灵活性高
D.交易方便
参考答案：B
---- Why weren’t you on line last night ?
---- Oh, my computer was broken and I had to have it ________ .
A．repaired
B．repairs
C．repairing
D．to repair
根据温病的发病迟早及初起是否见里热证，将其分为（）、（）.
