Ensure
来自Big Physics
late Middle English (in the senses ‘convince’ and ‘make safe’): from Anglo-Norman French enseurer, alteration of Old French aseurer, earlier form of assurer (see assure). Compare with insure.
wiktionary
From Anglo-Norman enseurer, from Old French seur(“sure”).
etymonline
ensure (v.)
late 14c., from Anglo-French enseurer, from en- "make" (see en- (1)) + Old French seur "sure" (see sure); probably influenced by Old French asseurer "assure." Compare insure. Related: Ensured; ensures; ensuring.