老师不应该打击学生的积极性，而是要鼓励他们。

Teachers should not ___discourage students, but encourage them instead.

老师劝阻学生在课堂上使用手机。

The teacher tried to ___discourage students from using phones in class.

医生劝我不要熬夜工作。

The doctor ___discouraged me from staying up late to work.