任
rèn
I v.
1) serve in a position
2) appoint to a position
3) allow
II n.
official post
III m.
term of office
美国总统一任四年。 One term of office for an American President is four years.
IV conj.
no matter (what/how)
任他怎么说，我都不信。 I don't believe him no matter what he says.
V b.f.
1) trust (信任)
2) any (任何)