Fed Rule Book

[Jake80]

Rule 2-5-1b - A fair ball is a batted ball which: contacts fair ground on or beyond an imaginary line between first and third base

What in the world does this mean? The way I look at it if the ball lands behind this imaginary line and has enough back spin to roll over the foul line before it has passed first or third it's obviously a foul ball. Or am I totally missing the point?


Rule 2-29-3 - When a runner adavances beyond a base to which he is forced without touching it, the force play remains.

Does this mean that if there is a runner at first and the ball gets by the fielder and the runner rounds second base but misses it that a throw to second would result in an out without an appeal or a tag if the ball beats him to the bag?