QUES: Continue writing.

Joel has recently bought a duck and doesn't know its sex so he asks Donald for help, because 
+++++++++
ANS: Donald is duck expert.


QUES: Continue writing.

Kenneth's diet was more successful than Hunter's, because 
+++++++++
ANS: Kenneth stopped eating fried food for a month.


QUES: Continue writing.

Since William was an expert at guitar while Neil was an amateur, 
+++++++++
ANS: William played their scaled with ease.


QUES: Continue writing.

Jennifer didn't know they were sleeping with a married man when they were with Samantha, because 
+++++++++
ANS:
Samantha had told them lies.