Faulty Parallel Structures
Among the mistakes that English language learners make on the sentence level, faulty parallel structures rank among the most frequent ones. Parallel structures express the same ideas in the same grammatical forms when they are in a list. If the grammatical forms are different, the parallelism is faulty.
Examples (Can you explain the meaning of these sentences? Which one is most likely to be correct?):
• My boyfriend likes playing computer games, football, and me.
• My boyfriend likes playing computer games, watching football and me.
• My boyfriend likes playing computer games, to watch football, and going out with me.
• My boyfriend likes playing computer games, watching football, and going out with me.
The fourth example is the only one with parallelism: the three activities are listed in the same way and make sense (each phrase begins with a gerund verb). In academic writing lists are often used to write thesis statements, to list examples, and to present different results. Writers must be careful with correct usage of parallel structures.