Robert enjoyed science experiments while Derrick was bored of them, so 
OPTIONS:
- Robert looked forward to physics class.
- Derrick looked forward to physics class.
Robert looked forward to physics class.

Jeffrey always put out food for the local hedgehog but William did not because 
OPTIONS:
- Jeffrey was a real animal lover.
- William was a real animal lover.
Jeffrey was a real animal lover.

Staying healthy in the winter was easy for Maria but not Natalie because 
OPTIONS:
- Maria ate a lot of fruits and vegetables.
- Natalie ate a lot of fruits and vegetables.
Maria ate a lot of fruits and vegetables.