“Look at these tracks. It be a wolf.” “Don’t be so sure. I think it be a fox.”
A. must; could
B. may; might
C. need; must
D. could; need
网友回答
(答案→)A. must; could
B. may; might
C. need; must
D. could; need
解析：根据 Don’t be so sure 可知前面一空应填must。第二空填的could表示推测，虽为过去式形式，但表示现在意义，语气较委婉，它与表推测的 can 主要用于否定句和疑问句不同，它可以用于肯定陈述句。