Meaning of -ES in English

-ES

1.

suffix forming plurals of nouns ending in sibilant sounds (such words in -e dropping the e) (kisses; cases; boxes; churches).

Etymology: var. of -S(1) 2.

suffix forming the 3rd person sing. present of verbs ending in sibilant sounds (such words in -e dropping the e) and ending in -o (but not -oo) (goes; places; pushes).

Etymology: var. of -S(2)

Oxford English vocab.      Оксфордский английский словарь.