is it possible to change to into against or against into to in this circumstance? 1)I opposed a barrier against a flood 2)I opposed violence to violence I saw this sentence. The first sentence shows there is against and the second sentence shows there is to. Here is what i wonder about. I opposed a barrier "to" a flood I opposed violence "against" violence. The preposition "To" means "to indicate who or what an action or a feeling is directed towards." The preposition "against" means to move in the opposite direction. The above two sentences is right? is it possible to change to into against or against into to in this circumstance?