tsukarete ita node, densha de nete oriru eki o norisugoshite shimaimashita.

Because I was tired, I fell asleep on the train and missed my stop.

Breakdown of tsukarete ita node, densha de nete oriru eki o norisugoshite shimaimashita.

• を: direct object particle
• で: location particle
• 電車でんしゃ: train
• 駅えき: station

Questions & Answers about tsukarete ita node, densha de nete oriru eki o norisugoshite shimaimashita.

Why is it 疲れていた instead of just 疲れた?

疲れていた is the past progressive/state form of 疲れる.

Here it means something like:

• I was tired
• I had become tired and was in that state

By contrast, 疲れた often means got tired or was tired in a simpler way, but 疲れていた emphasizes the ongoing condition at that time.

So in this sentence, 疲れていたので naturally sets up the background:

• Because I was tired...

What does ので mean here, and how is it different from から?

ので means because, since, or as.

In this sentence:

• 疲れていたので = because I was tired

Compared with から, ので often sounds:

• a bit softer
• more explanatory
• slightly more formal or neutral

So:

• 疲れていたから = also correct, a bit more direct
• 疲れていたので = sounds smoother and more like giving a reason calmly

Why is there no subject like 私 in the sentence?