Parallelism is the process of repeating a grammatical form in the sentence. Each idea must follow the same grammatical pattern. In this question When things go wrong, Carl tends to brood for hours and to blame others is a correct option because it is grammatically correct parallelism. After watching some TV, I was talking to my daughter and read e-mail is not an example of parallelism because of the irrelevance of the tenses. The school was closed not only because of the snow and ice but also because of the lack of heat is parallelism because we have the same grammatical structure in each part with this conjunction. The ice was a greater problem for the electrical power company than for the natural gas company - In this clause of comparison the structure of parallelism is also correct.
