Is a complete sentence, with a subject $($system$)$ and predicate $($intended result, action or condition$)$

Identifies only one requirement; does not include the words "and," "also," "with," and $"$or$."$

States what tasks the system will support or perform

Includes a measure or metric that can be used to determine whether the functional requirement is met $($time or quantity$),$ where appropriate

Is stated in positive terms and uses "must" $($not "may" or "should"$)$; e$.$g$.,$ "the system must xxxx$"$ not "the system must not xxx$"$

Avoids the use of terms that cannot be defined and measured, such as "approximately," "robust," "user friendly," etc.

Must be testable; that is$,$ there must be some way to test the system to determine whether the requirement is met