Mr. Andrew taught his students how to develop the basic skills in the physics class, everything through jokes and experiments.
A. to explain
B. explained
C. explaining
D. explains
网友回答
A. to explain
B. explained
(答案→)C. explaining
D. explains
解析：考查分词做状语用法。本题的动词explain与句子主语Mr. Andrew之间构成主动关系，故使用现在分词的形式做状语。A项不定式表示的是未来的动作。故C正确。