Complex sentence: Fred rushes to the rest of the kids and Bulk and Skull, celebrating at Ernie's and tells them of the situation, together they board the City's monorail and head to the construction site to save their parents.
Split into simpler sentences: Fred rushes to the rest of the kids and Bulk and Skull, celebrating at Ernie's and tells them of the situation. Together they board the city's monorail and head to the construction site to save their parents.