Complex sentence: By the end of the second season, it had slipped to 50th but was renewed for a third season, for which ABC moved the show to Friday nights at 8:00 p.m. as part of its "TGIF" comedy line-up.
Split into simpler sentences: By the end of the second season, it had slipped to 50th but was renewed for a third season. For its third season, ABC moved the show to Friday nights at 8:00 p.m. as part of its "TGIF" comedy line-up.