Notes: Parallel Structure | Writing for Academic IELTS PDF Download

Parallel structure is when you balance the grammatical structures of words, clauses, sentences, or phrases in your writing.
They are important for any kind of writing and speaking in order to maintain coherency.
We make words or phrases parallel when we are writing things in a list or series, and each word must have the same grammatical form.

• For words, nouns are balanced with nouns, adjectives with adjectives, verbs with verbs, gerunds with gerunds, and so on.
• For phrases, prepositional phrases are balanced with prepositional phrases, infinitive phrases with infinitive phrases, and gerund phrases with gerund phrases.

The coordinating conjunction ‘and’ is usually used to connect the parallel items, but other coordinating conjunctions such as ‘or’ and ‘nor’ may be used.

Correlative conjunctions such as 'both/and', 'neither/nor' and 'whether/or' are also used as connectors.

Examples of Parallel Structure

1. Infinitives / Gerunds

• She wants to go to England and studying at the London School of Economics. (WRONG)
• She wants to go to England and study at the London School of Economics. (CORRECT)

The first sentence is wrong because the first item in the list, to go, is an infinitive, but the second item, studying, is a gerund. In order to correct it, studying has been changed to an infinitive.

2. Adverbs

• John ensured that he gave his two minute talk confidently, effectively and persuasive. (WRONG)
• John ensured that he gave his two minute talk confidently, effectively and persuasively. (CORRECT)

The first sentence is incorrect as the last item in the series, persuasive, is an adjective, whereas the first two items are adverbs. The second sentence has been corrected by changing persuasive to the adverb, persuasively.

3. Adjectives

• The room was comfortable, airy, and it was not dirty. (WRONG)
• The room was comfortable, airy, and clean. (CORRECT)

The first sentence is incorrect, since the first two items in the series, comfortable and airy, are adjectives, whereas the last item, it was not dirty, contains a verb. The second sentence has been corrected by changing it was not dirty to the adjective clean.

4. Infinitive Phrases

• I can't decide whether to take a bus or riding my bicyle to work. (WRONG)
• I can't decide whether to take a bus or (to) ride my bicyle to work. (CORRECT)

The first sentence is wrong because an infinitive and gerund phrase have been mixed together. The second is correct because they are both infinitive phrases.

5. Prepositional Phrases

• He climbed the rock, up the wall, and onto the roof. (WRONG)
• He climbed over the rock, up the wall, and onto the roof. (CORRECT)

The first sentence is not parallel since the first word, the rock, does not have a preposition, but the next two words in the list have. It can be corrected by placing the correct preposition, over, before climbed.