Problem: Continue the following story.

Brian showed Donald how to prepare glycerol stock since 
Here's how I want to continue it: Donald had never made it before.

Problem: Continue the following story.

In gym class, Kayla was known to be in shape while Rebecca was not because 
Here's how I want to continue it: Kayla was a athlete.

Problem: Continue the following story.

Jen bought new glass bottles for her baby to replace the plastic bottles she wanted to be able to see the milk. The 
Here's how I want to continue it:
glass bottle  was clear.