Better:
Player enters desired screen name for chatting.
Weak:
User selects desired option "vs. Time" or "vs. Computer"
System places a check next to desired option.
Better:
User selects a "timed" game.
System displays a clock and shows elapsed time during play.
Weak:
System displays menu with "Start Game," "Watch Demo," "View
Hall of Fame," and "Quit" options.
Player selects a menu choice.
if Player chooses "Watch Demo" system displays Watch Demo menu.
...
Better:
Omit entirely. replace with separate use cases for each function.,
E.g. Watch Demo Use Case
System displays animated demo of game play.
Player may interrupt to stop demo at any
time.