It’s not polite to make fun of others.

 Mary ______ a bag _______ school.

--- Jack, could you help me ________ these pictures on the blackboard? It may help us know more about the hazy weather. (雾霾) --- With pleasure.

---At present, one of the best ways to study is working in groups.---More chances ___________ to students to learn from each other.

 He doesn’t like his job. He often ________ it.