Complex sentence: In March 1890 Yeats joined the Hermetic Order of the Golden Dawn, and with Ernest Rhys Hone (1943), 83 co-founded the Rhymers' Club, a group of London-based poets who met regularly in a Fleet Street tavern to recite their verse.
Split into simpler sentences: In March 1890 Yeats joined the Hermetic Order of the Golden Dawn. That same year Yeats and Ernest Rhys Hone (1943), 83 co-founded the Rhymers' Club, a group of London-based poets who met regularly in a Fleet Street tavern to recite their verse.