Complex sentence: These Universes stay in existence for 311 trillion, 40 billion years and then Maha Vishnu exhales and these Universes are destroyed and merged back into Him.
Split into simpler sentences: These Universes stay in existence for 311 trillion, 40 billion years. Afer a period of 311 trillion, 40 billon years, Maha Vishnu exhales and all of these innumerable Universes are destroyed and merged back into Him.