Page with semantically and nonsemantically varied text

OK: An HTML tag is a symbol or pair of symbols that creates an element.

Defect 1: A tag is a symbol or pair of symbols that create an element.

OK: Do not use the font element.

Defect 2: Never use the font element.

OK: It is usable, and, more importantly, accessible (a11y).

Defect 3: It is usable, and, more importantly, accessible.

OK: This situation is rare and unlikely to apply to you.

Defect 4: This situation is rare and probably does not apply to you.