He laied down as comfortably as he could, with his elbows resting on pine needles and the barrel of the machine gun laying on the trunk of a fallen tree. He laid down as comfortably as he could with his elbows resting on pine needles and the barrel of the machine gun lying on the trunk of a fallen tree.

lied is not telling the truth. When you get down in a horizontal position (past tense) it is 'laid'. If you are are already horizontal on the floor the past tense is 'lay', present participle 'lying'.

He lieday down as comfortably as he could, with his elbows resting on pine needles and the barrel of the machine gun laying on the trunk of a fallen tree. He lay down as comfortably as he could, with his elbows resting on pine needles and the barrel of the machine gun laying on the trunk of a fallen tree.

He lieday down as comfortably as he could, with his elbows resting on pine needles and the barrel of the machine gun laying on the trunk of a fallen tree. He lay down as comfortably as he could, with his elbows resting on pine needles and the barrel of the machine gun laying on the trunk of a fallen tree.

lie, lay, has lain → takes no direct object lay, laid, has laid → always takes a direct object

The enemy officer would arrive following the horses’ tracks, and he would be less than twenty meters away from where Robert had positioned himself. The enemy officer would arrive following the horses’ tracks, and he would be less than twenty meters away from where Robert had positioned himself.

The enemy officer would arrive following the horses’ tracks, and he would be less than twenty meters away from where Robert had positioned himself. The enemy officer would arrive following the horses’ tracks, and he would be less than twenty meters away from where Robert had positioned himself.

The enemy officer would arrive by following the horses’ tracks and he would be less than twenty meters away from where Robert had positioned himself. The enemy officer would arrive by following the horses’ tracks and he would be less than twenty meters away from where Robert had positioned himself.

At that distance, it would be impossible to miss. At that distance it would be impossible to miss.

The enemy officer was lLieutenant Barrendo. The enemy officer was Lieutenant Barrendo.

Lieutenant Barrendo is a name with title so Lieutenant has a capital.

The enemy officer was lLieutenant Barrendo. The enemy officer was Lieutenant Barrendo.

In English, titles are also capitalized.

The enemy officer was lLieutenant Barrendo. The enemy officer was Lieutenant Barrendo.

He had arrived from the farm and had been ordered to close in on the soldiers thatwho were taking shelter near the top of the mountain. He had arrived from the farm and had been ordered to close in on the soldiers who were taking shelter near the top of the mountain.

For people, use "who."

Barrendo and his men had overexerted their horses, and they had had to make a detour when they arrived at the damaged bridge. Barrendo and his men overexerted their horses, and they had to make a detour when they arrived at the damaged bridge.

Can keep the first "had", but I think it sounds better without it.

Barrendo and his men had overexerted their horses, and they had had to make a detour when they arrived at the damaged bridge. Barrendo and his men had overexerted their horses, and they had had to make a detour when they arrived at the damaged bridge.

Barrendo and his men had overexerted their horses andso they had had to mtake a detour when they arrived at the damaged bridge. Barrendo and his men had overexerted their horses so they had to take a detour when they arrived at the damaged bridge.

They had had to cross the gorge higher up the mountain and then go down again across the thick forest. They had to cross the gorge higher up the mountain and then go down again across the thick forest.

They had had to cross the gorge higher up the mountain and then go down again acrossthrough the thick forest. They had had to cross the gorge higher up the mountain and then go down again through the thick forest.

"Across" seems less idiomatic. My guess for why would be that "across" is used more for situations where the journey is relatively easy.

They had had to cross the gorge higher up the mountain and then go down again across the thick forest. They had to cross the gorge higher up the mountain and then go down again across the thick forest.

Their horses were sweaty and exhausted, to the point that they had to be forced to move on. Their horses were sweaty and exhausted to the point that they had to be forced to move on.

Their horses were sweaty and exhausted, to the point that they had to be forcedforce was needed to get them to move on. Their horses were sweaty and exhausted, to the point that force was needed to get them to move on.

This is technically correct, but I would reword the last bit as "had to be forced" sounds vague in the context of working animals.

Their horses were sweaty and exhausted, to the point thatwhere they had to be forced to move on. Their horses were sweaty and exhausted to the point where they had to be forced to move on.

When Barrendo arrived, he had a very stern look on his face. When Barrendo arrived he had a very stern look on his face.

His machine gun was resting on his saddle, underneath his left arm. His machine gun was resting on his saddle, underneath his left arm.

Is the gun resting on the saddle or underneath his left arm?

His machine gun was resting on his saddle, underneath his left arm. His machine gun was resting on his saddle underneath his left arm.

His machine gun was resting on his saddle, underneath his left arm. His machine gun was resting on his saddle, underneath his left arm.

This doesn't quite make sense to me: you would assume that his hands are holding the reins, but "underneath" here implies that he is holding onto the gun.

His machine gun was resting on his saddle, underneath his left arm. His machine gun was resting on his saddle underneath his left arm.

He waited until Barrendo reached a spot in which the sun shoined the brightest becaus, since there was a clearance in the forest. He waited until Barrendo reached a spot in which the sun shined the brightest, since there was a clearance in the forest.

I think "since" works better in this context, I'm not really sure how to explain why though.

He waited until Barrendo reached athe spot in which the sun shone the brightest because there was a clearanceing in the forest. He waited until Barrendo reached the spot in which the sun shone the brightest because there was a clearing in the forest.

He has reached a particular spot so 'the'.

He waited until Barrendo reached a spot in which the sun shone the brightest because there was a clearanceing in the forest. He waited until Barrendo reached a spot in which the sun shone the brightest because there was a clearing in the forest.

Robert could feel his heart thumping against the pine needles on which he was laying. Robert could feel his heart thumping against the pine needles on which he was laying.