Documentation Guidelines - Requirements Engineering and Management for Software Development Projects - page 236

A.3.7 Usage of Words

Here are the guidelines for using articles:

A.3.7.1 Articles

AN—The rule governing the use of article 'an' is phonetic and not orthogonal. The
article 'An' is used before vowels and a silent 'h'. Examples:

1. an eyelet
2. an 18th century practice
3. an heirloom''

A—The article 'a' is used before all consonants and also before vowels preceded
by the sound 'y' or 'w'. Examples:

1. a unit
2. a one-room
3. a eulogy
THE—The definite article 'the' is applied to an individual object or objects
mentioned earlier in the text or already known, or contextually particularized.
When in doubt, the answer to 'what' or 'which' generally clarifies whether 'the' is
required or not. Examples:

1. The software developed at Microsoft is commercial in nature. Which software?
'The' software developed at Microsoft.

The definite article 'the' should not be used when objects are referred to in
general or by an undefined sense. Example:

1. India, in comparison with other countries of the world, ought to have 20 million cars.

a. Which countries? Other countries in general.

A.3.7.2 AND/OR

The use of the expression 'and/or' is not recommended except in tables. Examples:

1. NEMA and/or IEEE abbreviations may be used—NOT RECOMMENDED
2. NEMA abbreviations or IEEE abbreviations may be used—RECOMMENDED

A.3.7.3 Usage of 'etc.'

Use of 'etc.' shall be avoided as far as possible. If it is found absolutely necessary
to use ''etc.'', it should be used after three or more nouns without the conjunction
'and'. In particular, 'etc.' shall not be used after a sequence introduced by
expressions like 'for example' and 'such as'.