Complex sentence: It had a worldwide opening weekend of $86.1 million, and reached the summit of the worldwide box office once, on its eleventh weekend (Feb 4--6,2011), with $24.9 million.
Split into simpler sentences: It had a worldwide opening weekend of $86.1 million. It reached the summit of the worldwide box office once, on its eleventh weekend (Feb 4--6,2011), with $24.9 million.