Complex sentence: He returned to the First Division in 1912 with Woolwich Arsenal, but made sparing first team appearances and predominantly played in the South Eastern League with the club's reserve team, scoring 9 goals in 16 appearances.
Split into simpler sentences: He returned to the First Division in 1912 with Woolwich Arsenal. As so he mainly played in the South Eastern League with the club's reserves, with whom he scored 9 goals in 16 appearances.