n. [U] (fml.) a way of behaving that people consider to be correct
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vt. (usu. passive) (be / feel ~d to do sth.) to make sb. feel that it is necessary to do sth.
n. [U] a feeling of being grateful to sb. for sth.
vt. to formally or officially tell sb. about sth. or give them information
a. usual in a particular society or situation
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