【题目】Professor Smith is very kind. You can turn to him for help as long as he is_________.
A.activeB.confusedC.availableD.busy
在线课程【答案】C
【解析】
考查形容词词义辨析。句意：史密斯教授非常友善。只要他有空你都可以向他求助。A. active积极的；B. confused感到困惑的；C. available有空的；D. busy繁忙的。根据You can turn to him for help可知，此处用“有空的”符合语境，故选C项。