sentence: The wind last night was able to knock over the old oak tree in the yard, the 
complete: tree was too weak.

sentence: Dennis had a much higher testosterone level than Christopher, so 
complete: Christopher started to worry about being able to have children.

sentence: Lindsey had access to the internet at home and Cynthia did not, and because of this, 
complete:
Lindsey spent a lot at home researching their paper.