引起霍乱患者的剧烈腹泻的原因是（）
A.神经氨酶
B.血凝素
C.霍乱内毒素
D.霍乱肠毒素
E.菌体裂解
参考答案：E
We have received news（）that the wool market on your side is showing signs of recovery.
A.to an effect
B.to this effect
C.to that effect
D.to the effect
简述汽油机两大机构和五大系统，柴油机两大机构和四大系统？
