Ben was busy taking a training class____
题型:选择题
问题:
Ben was busy taking a training class ______ we had to wait for himfor half an hour. [ ]
A. so
B. if
C. or
D. but
Ben was busy taking a training class ______ we had to wait for himfor half an hour. [ ]
A. so
B. if
C. or
D. but