Make The Marinade: Combine olive oil, red wine vinegar, soy sauce, garlic, oregano, lemon juice and zest (from 1 lemon) in a bowl. Whisk until blended, and oil and vinegar are fully incorporated. (**Cut remaining lemon in half crosswise and set aside for grilling and garnishing dish later).

IMPORTANT TIP: If you're making the full recipe (using 4 swordfish steaks), pour marinade into a large, shallow dish. Make sure dish is large enough to place the swordfish in it, in a single layer. If you're making only 1 or 2 swordfish steaks, pour marinade on a large, shallow plate, big enough to hold the fish steak(s).

Place swordfish steak(s) in marinade; turn them over so all sides are lightly coated. Let fish marinate for 15 minutes total (no longer!), turning it over halfway through the marinating time, then remove fish from the marinade.

Prepare gas or charcoal grill by cleaning grill grates, then oiling them well so fish doesn't stick. Heat grill to Medium-High temp. (on gas grill temp. should be 375°- 400°F.). Place swordfish directly onto hot, oiled grill. Cook for 4-5 minutes, without moving the fish, to get good sear marks and browning.

Carefully turn fish to the other side; continue cooking it another 4-5 minutes OR until fish reaches an internal temp. of 135°F. on a digital thermometer. When you flip the fish over, add reserved cut lemon halves to the grill (cut side facing down). Let them sear while second side of swordfish cooks. Once done, remove fish and lemons from the grill; place on a platter. Cover loosely with foil. Let fish "rest" 5 minutes before serving.