?使某人誓守秘密

... swear someone to secrecy 使某人誓守秘密... bind someone to secrecy 使某人誓守秘密... under the seal of secrecy 保证严守秘密...

?使某人严守秘密

... in the secrecy of one's own heart 在心灵深处 bind someone to secrecy 使某人严守秘密 un-der (the) seal of secrecy 保证守秘 ...