问题补充:
the majority of people you will meet when travelling are sure to be friendly, there are dangers-theft being the most common.
A. Since
B. Unless
C. While
D. Once
答案:
A. Since
B. Unless
(答案→)C. While
D. Once
解析:考察连词辨析。A自从,既然;B除非,如果…不;C尽管,当…时;D一旦;句意:尽管在你旅行的时候所遇见的人当,大部分都是友好的,但是也有一些危险。故C正确。