Do these sentences mean the same: "I sat watching the rain" vs "I sat while I was watching the rain."

Question

1- I sat watching the rain.

2- I sat while I was watching the rain.

In the beginning, I thought the two sentences were the same, 1st one being a shortened form the 2nd one.

However, after I learnt about participles functioning as adverbs, I got confused and thought these sentences might not be the same.

So, here is what I now think that the sentences mean:

1- "I sat watching the rain". I think it means "I sat sometime in the past, and during this action of sitting, I watched the rain. In other words, the sentence can be an answer to the question: A: "How did you spend time when you sat?". B: I sat watching the rain.

2-"I sat while I was watching the rain.". I think it means I had been watching the rain for some time in a standing position, then I got tired, and I decided to sit down". It seems that the sentence can be an answer to the question: A:"When did you decide to sit?". B: I sat while I was watching the rain. So the sentence is not about how I spent time during the action of sitting, but when the action of sitting happened.

This is what I concluded. So, do these 2 sentences have the same meaning or do they emphasize different aspects?

Answer 1

Your interpretation of the two sentences and their difference is correct. Although (2) could be taken as meaning the same as (1) depending on the wider context.

As Kate Bunting says, the second one is not something a native English speaker would normally say. They might use something like

Whilst [I was] watching the rain, I sat down.
As I watched the rain, I sat down.

Answer 2

Interesting question!

In the first example, there's much less emphasis on the act of sitting down. 'To sit' doesn't necessarily mean to sit down (as in a chair). See the 3rd definition in the Oxford Advanced Learner's Dictionary ('to be in a particular place'). This use of the word would be much more likely to refer to an object (a car, a box, a pile of papers...), but could theoretically also refer to a person. So you could even 'sit' watching the rain while standing up!

The second sentence could mean that you physically sat down at some point during a storm, which you had already been watching for some time while standing up (the example you give in your question). It could equally mean you watched the rain, while sitting down for the entirety of this time (the definition you give to the first of your sentences)