obligations
If you have an obligation to do something, it is your duty to do that thing.
When teachers assign homework, students usually feel an obligation to do it.
老师布置家庭作业时,学生们通常感觉做作业是一种义务。
If you have an obligation to a person, it is your duty to take care of them or protect their interests.
The United States will do that which is necessary to meet its obligations to its own citizens.
美国会尽其对国民应尽的义务。
without obligation
In advertisements, if a product or a service is available without obligation, you do not have to pay for that product or service until you have tried it and are satisfied with it.
If you are selling your property, why not call us for a free valuation without obligation.
如果你打算出售房产,为什么不打电话让我们做个免费的估价呢。