Question

I ________ that the earth moves around the sun

1. A.
   often doubt
2. B.
   never doubt
3. C.
   sometimes doubt

Answer 1

B
考查doubt的用法。doubt用于肯定句时，宾语从句用whether引导；用于肯定句时，用that引导宾语从句。句意“我从不怀疑地球是围绕太阳转的。”根据that可知，本句是否定句。故选B。