contribute something (to someone) (for someone or something)
to donate something to someone for the benefit of someone or something. I hope you will contribute at least a dollar to Mary for Tom's birthday present. Will you contribute a dollar for Tom to Mary when she comes around? Can you contribute a dollar for the gift?
contribute to something
1. to donate something to some cause. Please contribute to the fund for the needy.
2. to add to or exacerbate something. The dry weather contributed to the failure of the crops.