Complex sentence: The main arch of the bridge is 120 m long, weighing 300 tonnes, 32 m tall with its top 40 m above the Tees and the short arch is 60 m long and 16 m tall.
Split into simpler sentences: The main arch of the bridge is 120 m long, weighing 300 tonnes, 32 m tall with its top 40 m above the Tees. The short arch is 60 m long and 16 m tall.