按密鑰的使用個(gè)數(shù)，密碼系統(tǒng)可以分為()。
A、置換密碼系統(tǒng)和易位密碼系統(tǒng)暫無解析
Wewouldliketotakethis______toestablishbusinessrelationswithyou.
Indentisoftenusedby______or______inothercountries.
Pleaseseetoitthatthegoodsweorderedareshippedassoonasthecoveringletterofcredit______you.
Weagreetotheamendmentstothecontract_____requestedinyourletterofMay5.
Countersampleismadeby()whichcanhelpavoiddisputesoverthequalityofgoodsinthefuturetransaction.
