Problem: How does the sentence end?

James had his shirt stained with blood and he wore a jacket over it  because the 
Answer: shirt is dirty.

Problem: How does the sentence end?

Felicia managed to avoid an upper respiratory infection that year, but not Betty, because 
Answer: Betty had made sure to avoid a flu shot.

Problem: How does the sentence end?

Elena is writing a contingency plan for Katrina, because 
Answer: Elena knows how to do it.

Problem: How does the sentence end?

The computer needed a new monitor, but the keyboard was fine, because the 
Answer:
monitor was very old.