It’s difficult that we shouldn’t spend all our time our favorite hobby.
A. to remember, in
B. to remember, on
C. remember, in
D. remembering, on
网友回答
A. to remember, in
(答案→)B. to remember, on
C. remember, in
D. remembering, on
解析：考查句型It’s+ adj +to do sth，it作形式主语，真正的主语是后面的不定式，短语：spend time on sth，把时间花在某物上，句意：记住我们不应该把我们所有的时间 我们的业余爱好上是很难的。故选B。