Final answer:
Dorine plans to unite Mariane, Valère, and the family against the forced marriage to Tartuffe by exposing Tartuffe's true nature to Orgon.
Step-by-step explanation:
Dorine's plan to prevent Mariane and Tartuffe's wedding in Molière's play involves uniting Mariane's true love, Valère, and her family against the forced marriage. Dorine, a sharp-witted maid, sees through Tartuffe's hypocrisy and devises a scheme to disclose his true nature to Orgon, Mariane's father, who is deceived by Tartuffe's guise of piety. By doing so, she hopes to convince Orgon to cancel the wedding and allow Mariane to marry Valère instead.