Explanation:

- Marriage by exchange: Involves swapping of siblings in marriage between two families to avoid dowry, but it might be prohibited due to potential inequalities or exploitation.

- Marriage by trial: Partners live together to test compatibility before formalizing the union.

- Marriage by intrusion: One party insists on being accepted as a spouse, sometimes without consent.

- Marriage by service: Involves working for a future in-law family, often to earn the right to marry a daughter.

Marriage by exchange is not accepted among Khasis.

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