Green Beret/Bridge at airshed
When you first attempt this stage, the lower level may appear very cluttered to you, and you might be inclined to feel that the upper path is safer, but this is not necessarily true. When you take the upper path, you'll have to make sure that you leap over the grenades that get launched upward from the ground below. You may also feel compelled to take the upper route to hit the supply runners, who mainly offer grenades in this level, but don't forget that they will climb down to you as well. Unlike the NES version, which uses combat specialists quite liberally, this is the first arcade level where they can present quite a challenge. Their lighter coats don't stand out as well, and they can take you by surprise. Don't forget that you can also simply run beneath them if you don't stop.
Once you reach the fence, enemies will begin to swarm you in every direction. You still have the choice between the ground route, and an upper route along the fence, but the decision is a little tougher. For one thing, the difference in height is much greater, and you'll have to remain on the ladder longer which makes you vulnerable. For another, a new type of weapon's enemy will appear on top of the fence, and they like to toss grenades at you. Either way you go, you will encounter parachute soldiers once the fence is finished. You will eventually reach the woods which also has two layers to run along. It's not as long as the other sections, and you will soon reach the bridge where the stage end fight occurs.
Once you reach the bridge, the enemy will attack you with a squadron of three one-man gyrocopters. These copters will hover in the air and lob grenades down at you. While they are up there, you cannot harm them, but on occasion, they will fly down low in an attempt to mow to down. When they do, this is your chance to jump up and slash the copters with your machete. One hit is all it will take to cause a short circuit and destroy the copter and it's pilot. Focus on one at a time, and don't hesitate if you see two come down at once; stick to your target. Don't leap until you know it's safe to do so.
 NES differences
Grenade launchers are for some reason perched on top of the barrels so you have to jump up to attack them. A parachute soldier comes down very early in this level. The best strategy is to remain on the bottom level until he lands, and you attack the first supply runner. Climb the ladder to collect the rocket launcher, and remain on that level of the remainder of the first half. As you run along, don't stop; the grenades will lob safely over your head and the combat specialists will jump over you as well. You only have to worry about the men behind you. When you reach the fence, you will only encounter foot soldiers, gun soldiers, and combat specialist for the rest of the level. Watch out for land mines along the floor. (In the Japanese version, if you detonate the mines, you will find ladders that lead down to an underground passage. It's not necessarily a short cut, but the layout of the passage works to your advantage.) The gyrocopters in this version follow along the same slow zig-zag path. You will have to dodge their grenades until the first one is low enough for you to jump up and attack on the right side. Be patient, so don't hang too close to the right edge of the screen; foot soldiers appear from either end on occasion.