变异链球菌的胞外酶有：（）、（）、（）、（）。
参考答案：葡糖基转移酶、果糖基转移酶、蔗糖酶、葡聚糖酶。
(a) In relation to the English legal system distinguish between the following:(i) Criminal law;(ii) Civil law. (5 marks)
I'll never understand how it _____ that he still insisted on going there alone after being told about the
possible danger. [ ]
A. came about
B. came across
C. came out
D. came up
