Complex sentence: Along with her return, Nakashima is going to release her new single "Dear" on April 29th and is starting her concert tour "MIKA NAKASHIMA CONCERT TOUR 2011 THE ONLY STAR" at the end of April.
Split into simpler sentences: Along with her return, Nakashima is going to release her new single "Dear" on April 29th. Also, along with her return and her new single release, Nakashima is starting her concert tour "MIKA NAKASHIMA CONCERT TOUR 2011 THE ONLY STAR" at the end of April.