The teacher the students how to improve their writing skill since last term.
A. has told
B. is telling
C. has been telling
D. will have told
网友回答
A. has told
B. is telling
(答案→)C. has been telling
D. will have told
解析：考查时态。本题的关键词是后面的时间状语since last term，该短语通常和现在完成时使用，根据句意强调的是一直都在做某事，故使用现在完成进行时来强调。句意：自从上个学期到现在，老师一直都在告诉我们如何提高写作技巧。故C正确。