Englishfor English speakers
previous
Adjective
—
If something happened at a previous time, it happened before a particular time.
Last year, we lived in Seoul, but the previous year we were in Moscow.
previous
Preposition
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You use previous to refer to a time before something else.
The history of this site previous to the seventeenth century is unknown.
Four years previous, he had been sick for a month.
obligation
Noun
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An obligation is a duty, something you must do.