Opponents say the plan will further weaken the institution of marriage.

反对者表示，这项提案将进一步弱化婚姻制度。

We no longer need the institution of marriage to ensure the survival of our species.

我们已不再需要婚姻这种制度来保障种族的延续。

Because I need to protect the institution of marriage.

- 因为我需要保护婚姻制度。

The institution of marriage by capture, for instance, has puzzled many inquirers into the habits of primitive man.

例如， 俘虏婚姻制度让许多探究原始人习俗的人感到困惑。