Robot that searches for lights
In pseudocode:

LoopBlock (forever)
    MoveBlock (B and C motors, 75% power, forward, forever)
    -- unclear here, probably want to head for brighter light
    -- instead, just wait for 80%
    If LightSensorBlock (port 3, greater than, threshold 80%) Then
         MoveBlock (B and C motors, stop)
         WaitForBlock (time, 10 seconds)
    End If
End Loop