Verb (5-dan, す, intransitive)
1.  to obey;  to submit to;  to yield to;  to accept;  to abide by
2.  to serve (in the army, a prison sentence, etc.)
3.  to go into (mourning);  to observe
Verb (5-dan, す, transitive)
4.  to take (medicine, poison, etc.);  to drink (tea)