WB formatted for mac, can I copy onto it from a PC?

I’m meeting with an instructor of mine in a week and he has some materials he’d like to give me, and it’s a large quantity of files, so it won’t fit on my usb drive. It will fit on my WB My Passport, although that is formatted for mac and he has a PC. Will he be able to copy files onto it, or will it be read only? If it is read only, what should I do… should I just go out and buy a larger USB drive?