Complex sentence: Completed in 1999, it has become Fermilab's "particle switchyard" with three functions: it accelerates protons, it delivers protons for antiproton production, and it accelerates antiprotons coming from the antiproton source.
Split into simpler sentences: Completed in 1999, it has become Fermilab's "particle switchyard". It has three functions: it accelerates protons, it delivers protons for antiproton production, and it accelerates antiprotons coming from the antiproton source.