We’d better stay here a little longerhe turns up unexpectedly.A. althoughB. in caseC. sinc

问题补充：

We’d better stay here a little longerhe turns up unexpectedly.

A. although

B. in case

C. since

D. if only

答案：

A. although

(答案→)B. in case

C. since

D. if only

解析：考察连词辨析。A尽管；B以防…；C既然，自从；D要…就好了。句义：我们最好在待一会，以防他突然出现。根据句义说明B项正确。