certain obligation

基本解释

A good citizen has certain obligation to society.
一個好公民對社會有某些義務。
The possessor of registered trademark is the one who owns the registered trademark right and undertakes certain obligation according to the law.
注冊商標所有人是指對其注冊商標依法享有權利、承擔一定義務的商標注冊人。
If you are unhappy with a certain obligation or relationship you entered into some time ago, then decide whether you want to try to fix things or leave the deal or relationship altogether.
如果你對不久前開始的某個義務或關系感到不高興的話，決定是要嘗試去脩補還是要把這些事情或關系全部放下吧。

Germany, the most biofuelled nation in Europe, has replaced a tax break with a straightforward legal obligation for refiners to blend a certain proportion of biofuels into their wares.
ECONOMIST: Can biofuels save Europe, or the planet?
Calls give you the right, but not the obligation, to buy shares at a certain price.
FORBES: Magazine Article
It is the right, but not the obligation, to buy something at a certain price.
FORBES: Consider Your Options