Use is one thing, but what about contributions? It is confusing for me. If the project has GPL and MIT license I can't contribute GPL code to it, can I? Becaus

Use is one thing, but what about contributions? It is confusing for me. If the project has GPL and MIT license I can't contribute GPL code to it, can I? Because it has to be also MIT. Generally more restrictive license is more important in case of contributions. More permissive license is more important in case of use and modifications not contributed back. It is a fork welcoming licensing.