n.[(+on/upon)]

1. （税的）征收；施加（惩罚等）[U]
   Everyone grumbled at the imposition of new taxes.

   对征收新加的赋税人人都抱怨。

2. 征收的税；惩罚，负担[C]
   an imposition of 200 dollars on a coat

   对上衣收的二百美元税

3. 不公平的负担；不合理的要求[C]
   severe impositions on one's children

   对孩子太过严厉的要求

4. 强加[U]
   The film star became wild with anger over the imposition on her privacy.

   那位电影明星因私生活受到干预心头直冒怒火。

5. 利用；欺诈；哄骗[C]
   Would it be an imposition to ask you to mail this parcel?

   请你邮寄这个小包裹算是利用你吗？

n.

1. the action of imposing or of being imposed.
2. an unwelcome demand or burden.