1. 学生；小学生
    The pupils of a school are the children who go to it.

    e.g. Over a third of those now at secondary school in Wales attend schools with over 1,000 pupils...
           威尔士现在的初中生中有1/3以上的人就读的学校学生总数超过1,000人。
    e.g. Eleanor was a reluctant, anxious pupil.
           埃莉诺是个扭捏局促的小学生。

2. 弟子；门生
    A pupil of a painter, musician, or other expert is someone who studies under that expert and learns his or her skills.

    e.g. After his education, Goldschmidt became a pupil of the composer Franz Schreker.
           学业结束后，戈尔德施米特成了作曲家弗朗兹·施雷克尔的学生。

3. 瞳孔
    The pupils of your eyes are the small, round, black holes in the centre of them.

pupil的翻译