Parallelism

1. Parallelism is the repetition of a grammatical form within a sentence. It shows that two or more ideas have the same level of importance helps avoid repetition:
1. Sam has a pen in his bag, a pencil and he also has two books in his bag (no parallelism, incorrect)
2. Sam has a pen, a pencil and two books in his bag (with parallelism, correct)
2. Parallelism is used with equivalent grammatical elements joined by coordinating conjunctions:
1. My mother likes cooking and to read (incorrect)
2. My mother likes cooking and reading (correct)
3. It is also used with elements in lists or in a series:
1. This task can be done individually, in pairs, or can be done in groups of four (incorrect)
2. This task can be done individually, in pairs, or in groups of four (correct)
4. Parallelism is used with elements being compared:
1. She likes watching TV more than to read a book (incorrect)
2. She likes watching TV more than reading a book (correct)
5. It is used with equivalent grammatical elements joined by a linking verb or a form of the verb 'to be':
1. To learn is understanding the world (incorrect)
2. To learn is to understand the world (correct)
6. It is used with elements joined by linking words:
1. The teacher not only wants his students to keep quiet but also to do the task (incorrect)
2. The teacher wants his students not only to keep quiet but also to do the task (correct)