Translation of resistant in Spanish

Do you speak German? How many languages can you really speak? I know Russian, English, Italian and some Spanish. I want to learn more Spanish, let's try to do it together? I love this forum.
I will be creating an additional study with a student (his name is Juan), which may appear in local newspapers in the future (in English). However, this may take a couple of weeks too.
If you are spell checking my letters, that would be great. I would then do the same with your letters. Can you please correct this email too? I thank you in advance for helping my Spanish.