Problem: Continue the following story.

The plants stopped manufacturing robots and switched to cars, as the 
Here's how I want to continue it: robots were expensive to produce.

Problem: Continue the following story.

Jason got over their case of the flu before William did, because 
Here's how I want to continue it: Jason 's immune system was generally more healthy.

Problem: Continue the following story.

It was necessary to hit the iron with the sledgehammer after the 
Here's how I want to continue it:
iron got heated.