Latin plurals
Some are so common that we do not realise they are plurals: alumni, criteria.
However, many single forms look pedantic and put the reader off.
When referring to data, although it is technically plural, its use as singular or plural is optional but to be consistent.
Examples:
fora – use forums
formulae – use formulas
syllabi – use syllabuses
Paragraphs
Use one line return in between paragraphs. Do not indent at the beginning of paragraphs.
Keep paragraphs short, especially when writing for the web. If you are writing for a student audience, bear in mind that large blocks of text put readers off.
Redundancy
Try to avoid words which add nothing to the meaning of your sentence. You could end up with a redundant expression such as:
You can register now, or alternatively wait until July.
Pip is the chief protagonist of Great Expectations.
Tautology (grammatical)
A fault in style which can be defined as saying the same thing twice. Watch out for this if you are writing marketing copy you might be tempted to over-emphasise.
Examples:
Significant landmark.
Added bonus.