There are very few manual focus lenses made for the EOS mount, Tamron lenses are around in which you purchase the correct adaptall mount, and there are a couple of after market inexpensive telephoto lenses, but the rebal allows you to switch to manual focus mode and use the autofocus lens in manual focuse mode, there have been different canon mounts over the years, but the only ones that will fit the rebel are the EOS designated lenses, the FD and such even though a canon mount will not fit on the rebel, unless you find a adapter mount(expensive), then you will loose different features of the newer body, the Rebel models are actually pretty sophisticated cameras and have a lot of features available on them.

Dave