Problem: Continue the following story.

The car with the electrical motor was able to travel further than the car with the gas motor because the 
Here's how I want to continue it: gas motor car got worse mileage.

Problem: Continue the following story.

The old man said that Dennis needed a coffee every morning unlike Jeffrey, due to 
Here's how I want to continue it: Dennis being addicted.

Problem: Continue the following story.

The seeds that Leslie plants aren't as good as the ones that Brian used. 
Here's how I want to continue it:
Brian went to a reputable farm shop.