if err := DB.Model(&users).Association("Languages").Delete(users[0].Languages[0], users[1].Languages[1]); err != nil {
		t.Errorf("no error should happened when deleting language, but got %v", err)
	}

	AssertAssociationCount(t, users, "Languages", 2, "after delete")

	// Clear
	DB.Model(&users).Association("Languages").Clear()