Expressing "within" a period of time using "zai... nei"

"在 (a period of time) 内" may sound a bit redundant, since 在 means "in" and 内 means "within" or "inside," but it is a commonly used "sandwich pattern" which means "within (a period of time)."


在 + (a period of time) + 内

The period of time in this structure can be a clear-cut indicator of time (days, months, years) or it can be a more vague indicator of time (short amount of time, a lifetime).

See Also

Sources and further reading