Able to think only of my mother's surgery the next morning, I could not even eat my dinner, much less get any sleep, nor could I do my homework.
My Answer
First one is periodic sentence
Unable to eat dinner, do my homework, or get any sleep, I could think only of my mother's surgery the next morning.
Second in cumulative sentence
All I could think about was of my mother's surgery the next morning, unable to eat dinner,do my homework, or get any sleep.
Your first revision is fine.
Your second one is incorrect ... unless you mean that your mother's surgery was unable to eat dinner, do homework, or get any sleep!
Do you see why?
Right.
http://grammar.about.com/od/pq/g/periodicsenterm.htm
Great job identifying the sentence structures!
In the given passage, the first sentence is a periodic sentence. A periodic sentence is a sentence in which the main idea or the independent clause is placed at the end of the sentence. In this case, the main idea is "I could not even eat my dinner, much less get any sleep, nor could I do my homework," and it is placed at the end of the sentence after the dependent clause "Able to think only of my mother's surgery the next morning." By using a periodic sentence, the writer emphasizes the effect of the protagonist's preoccupation with their mother's surgery.
The second sentence is a cumulative sentence. A cumulative sentence, also known as a loose sentence, is a sentence structure in which the main idea or the independent clause comes at the beginning or in the early part of the sentence and additional details or phrases are added to the main idea. In this case, the main idea is "All I could think about was my mother's surgery the next morning," and the additional details or phrases are "unable to eat my dinner, do my homework, or get any sleep." By using a cumulative sentence, the writer adds information to the main idea, intensifying the reader's understanding of the protagonist's state of mind.
Overall, both types of sentences are effective in conveying the protagonist's overwhelming worry about their mother's surgery by emphasizing the actions they were unable to perform.