=1

便

biàn

plain informal suitable convenient opportune to urinate or defecate equivalent to 就 jiù: then in that case even if soon afterwards

=1

便

pián

used in 便宜 piányi used in 便便 piánpián used in 便嬛 piánxuān

=2

当

dāng

(onom.) dong ding dong (bell)

=2

当

dāng

to be to act as manage withstand when during ought should match equally equal same obstruct just at (a time or place) on the spot right just at

=2

当

dàng

at or in the very same... suitable adequate fitting proper to replace to regard as to think to pawn (coll.) to fail (a student)