Third person singular present tense of deprave; he/she/it depraves or corrupts morally.
From deprave + -s (third person singular present tense marker). In English, most verbs add -s for third person singular in present tense (he walks, she runs).
The -s ending for third person singular is so automatic that English speakers never think about it, yet it's a crucial marker showing who is doing the action and when.
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