chắc chắn đảm bảo bảo đảm giữ an ninh 
secure like: bảo đảm → →
Bitte verschicken Sie diese Mahnung per Einschreiben. ☊ 
Làm ơn hãy gửi bảo đảm lá thư cảnh báo này. ☊ (Lektion 126, Nr. 2522) Article 10 of the European Convention guarantees free speech. ☊ article ☊
rights and freedoms guaranteed by the constitution ☊ freedom ☊
They are demanding certain guarantees before they sign the treaty. ☊ guarantee ☊
We provide a 5-year guarantee against rust. ☊ guarantee ☊
a money-back guarantee ☊ guarantee ☊
guarantee (that)...: We cannot guarantee (that) our flights will never be delayed. ☊ guarantee ☊
They support the measures without reservation (= completely). ☊ reservation ☊