Clearing debris when off the green

Hey guys, i'm just wondering about the ruling when you're off the green, say on the fringe. Things like, if your pitch mark is OFF the green, on the fringe in front of your ball, can you repair it? If your pitch mark is ON the green between you and the flag, can you repair it? If you've come from the bunker and you have sand in front of your ball, can you clear it? And lastly is it ok to clear loose inpediments from your line both on and off the green?

Cheers guys,
Al

1) No. See Rule 13-2
2) Yes. See Rule 16-1c
3) Depends. See Definition of Loose Impediment. Then see 4) below
4) Yes. But see Rule 23-1 if your ball is in a hazard.

13-2 (part)
A player must not improve or allow to be improved:
• his line of play or a reasonable extension of that line beyond the hole, or
• creating or eliminating irregularities of surface,

16-1c
The player may repair an old hole plug or damage to the putting green caused by the impact of a ball, whether or not the player’s ball lies on the putting green.

23-1 Relief
Except when both the loose impediment and the ball lie in or touch the same hazard, any loose impediment may be removed without penalty.

Definition

Sand and loose soil are loose impediments on the putting green, but not elsewhere.