资料来源 : Webster's Revised Unabridged Dictionary (1913)

-'s \-'s\ [OE. -es, AS. -es.] The suffix used to form the
   possessive singular of nouns; as, boy's; man's. 's \'s\
   A contraction for is or (colloquially) for has. ``My heart's
   subdued.'' --Shak.