Complex sentence: Abbosali went to J.H.S.157 STEPHEN A. HALSEY Middle School as a seventh-grader and then he applied to International High School at Laguardia Community College.
Split into simpler sentences: Abbosali went to J.H.S.157 STEPHEN A. HALSEY Middle School as a seventh-grader. After completing Middle School, he applied to International High School at Laguardia Community College.