Check out Sylvan Learning Center's Grammar Quiz:
http://encarta.msn.com/encnet/depart...d=146>1=6065
Number 9 has no answer:
Choose the grammatically correct option.
a) Cats and dogs make good pets. Dogs are loyal and cats are clean.
b) Cats and dogs make good pets. Cats are clean and dogs are loyal.
c) Cats and dogs make good pets because they're clean and loyal.
Corrections:
a) Not parallel
b) Parallel - however the second sentence is a run-on as it is missing a comma. It should read:
Cats are clean, and dogs are loyal.
c) Missing a comma before "because"
-I called Sylvan and left a message. How HORRIBLE!