Parallelism

-The main issue of parallelism is when having a list in a sentence you have to make sure that all the items in the list are written in the same way. 

Examples: 

• A good attitude, being on time, and speaking effectively are good attributes.

This sentence is NOT parallel. The underlined part of the sentence is the list. Is every item in the list structured the same way? No. The error is in "A good attitude", because "being on time" and "speaking effectively" contain ing-forms, unlike "a good attitude". So the correct way to structure the sentence is: "Having a good attitude, being on time, and speaking effectively are good attributes"

• Many people in this country remember how they danced to the mambo music of the 1950s and listened to that era's Latin bands.

This sentence IS parallel. Are the items in the list structured the same way? Yes. both verbs are written in the past so there's no error.

• You should learn to cook, hire waiters, and start reading cooking books before opening your own restaurant.

This sentence is NOT parallel. Are the items in the list structured the same way? No. The error is in "start reading cooking books". The correct way to structure the sentence is "You should learn to cook, hire waiters, and read cooking books before opening your own restaurant." 

There are actually a lot of ways to structure the same sentence without creating an error in the parallelism. This sentence can also be structured as "You should start learning cooking, hiring waiters, and reading cooking books before opening your own restaurant." If you fully understand the lesson then you can come up with your own way to structure a sentence.

If you still don't understand the lesson you can check out this video: 

Now you understand the lesson and you can answer some exercises on this link: 

http://www.towson.edu/ows/exerciseparal.htm