obligation/ ɔblɪ'geɪʃən /

1.noun [c/u] 
责任

to have an obligation to do sth
有责任做某事
to have an obligation to sb (to do sth)
对某人有(做某事)的责任
to be under an obligation to do sth
有义务做某事
to be under an obligation to sb
对某人有义务
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