Different wordings in place of "mekudeshet", which are [not] valid: Kiddushin 5b, 5b-6b
What if the groom says to a second woman, after declaring marriage to the first, "And you" or "And you, too": Nedarim 6b
"Half" cases
If the groom says, "Marry half of me": Kiddushin 7a
If the groom says, "I want half of you to be married to me": Kiddushin 7a
If the groom says, "I'll marry half of you for half of a perutah, and the other half for the other half of a perutah": Kiddushin 7b
If the groom says, "I'll marry both halves of you for a perutah": Kiddushin 7b
If the groom says, "I'll marry half of you for a perutah and the other half for a perutah": Kiddushin 7b
If the groom says, "I'll marry half of you for a perutah today, and the other half for a perutah tomorrow": Kiddushin 7b
If the groom's father offers, "I'll pay for the marriage of both of your daughters to both of my sons for one perutah": Kiddushin 7b
Lack of commitment
If the groom says, "Marry me on condition that I am not obligated to provide food, clothing or sexual satisfaction: Ketuvot 56a-b; Kiddushin 19b; Bava Metzia 51a-b
If the groom says, "Marry me, effective after I convert", or "Marry me, effective after you convert": Ketuvot 58b; Bava Metzia 16b
If the groom says, "Marry me, effective after I am freed from my position as an eved kenaani", or "Marry me, effective after you are freed from your position as a shifchah kenaanit": Ketuvot 58b; Bava Metzia 16b
If the groom says, "Marry me, effective after your husband dies, or your sister [my wife] dies": Ketuvot 58b; Bava Metzia 16b
If the groom says, "Marry me, effective after your chalitzah": Ketuvot 58b; Bava Metzia 16b