Ensure that you construct parallel lists
A parallel list means that each item in the list has the same structure. For example, each item might:
- start with the same part of speech (noun, verb)
- use the same verb tense (present, past, future)
- use the same voice (active or passive)
- use the same sentence type (statement, question)
For example, in the bulleted list above, each item starts with a verb in the present tense and includes an example in round brackets.
Four basic types of lists
1. Lists of short items (without main verbs) should be introduced by a full sentence and have the following features:
- introductory colon
- no initial capitals
- no punctuation (very short items) or comma after each item
- a full stop at the end.
2. Lists in which each item completes the introductory sentence should:
- begin with the introductory colon;
- label each item with the appropriate bullet, number or letter;
- end each item with a semicolon;
- close with a full stop.
3. Lists in which all items are complete statements without a grammatical link to the introductory sentence should proceed as follows:
- introduce the list with a colon;
- label each item with the appropriate bullet, number or letter;
- start each item with a lower-case letter;
- end each one with a semicolon;
- put a full stop at the end.
4. Lists in which any one item consists of several complete sentences should be announced with a complete sentence and continue as indicated below:
- Introduce the list with a colon.
- Label each item with the appropriate bullet, number or letter.
- Begin each item with a capital letter.
- End each statement with a full stop.
This allows several sentences to be included under a single item without throwing punctuation into confusion.
References
E-Write. Writing for Online Readers.'How and Why to Make your Lists Parallel (And what does parallel mean?)'. Retrieved from http://www.ewriteonline.com/how-and-why-to-make-your-lists-parallel-and-what-does-parallel-mean/