attest
v.
1590s, from Middle French attester (Old French atester, 13c.) "affirm, attest," from Latin attestari "confirm," literally "bear witness to," from ad- "to" (see ad-) + testari "bear witness," from testis "witness" (see testament). Related: Attested; attesting.
〔李〕[at-(ad-);testv.] v.证明； 表明； 使宣誓 ←test (L testis)=witness 证人