Using gender-specific language can be ambiguous and, because the word he is no longer widely recognised as gender-neutral, can take the focus away from the subject when it jars the reader out of the reading flow.

Using they or their to replace he or she is becoming commonly accepted in informal writing.

Using he or she is also fine, as long as we don't use the phrase every time we need to use a pronoun. Try re-writing the sentence to avoid having to use a pronoun at all.

Making the subject plural can sometimes be a simple solution. Don't use constructs such as he/she or (ack!) s/he.

For example:

If a student is late in enrolling, he must pay an additional fee.

Try using one of these gender-neutral sentences instead:

If a student is late in enrolling, they must pay an additional fee. If a student is late in enrolling, he or she must pay an additional fee. Any student who is late in enrolling must pay an additional fee. Students who are late in enrolling must pay an additional fee.

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