Base on
Definition 1 of 2
Pro Tip 1/3Origin Importance
Understand that what is 'based on' serves as the starting point or inspiration for something. 
This theory is based on early scientific research.
Pro Tip 2/3Facts Matter
The phrase often implies reliance on factual evidence for constructing something. 
Her thesis is based on empirical data.
Pro Tip 3/3Creative Adaptation
'Based on' indicates adapting a true story for artistic purposes, not an exact retelling. 
The film is based on a true event.