问题补充：
he was, he still went on with his work.
A. Tired although
B. Tiring as
C. Tired though
D. While tired
答案：
A. Tired although
B. Tiring as
(答案→)C. Tired though
D. While tired
解析：考查倒装句,as/though可以用于倒装句，结构是：adj/adv/v/n+as/though+主谓，这句话就是提前的形容词，句意是:虽然他很累，他还是继续工作。选C。
