て form and adverbial meaning

Question

While reading I sometimes come across some sentences like

包丁を使ってたまねぎを切った。　

Where 使って is word just like an adverb which modifies 切る.

So I looked up a little more about the Te form and I found this:

付帯状況

Which I think it shows how you do the main verb using the Te form verb before it as an adverb which modifies the main verb.

Could someone give me a good explanation about Te form and 付帯状況?
Is the Te form just an adverb?
Or is it like a relative clause but instead of making a relative about a noun it makes an adverbial clause which shows how the next verb is done?

(The the form somehow reminds me of V1ことで...V2, by doing (through) V1 I do V2 or V1 is how I do V2. This is just how my mind sees it and I don't claim that is correct, but can someone tell me if I am wrong?)

Answer 1

Yes it's adverbial in relation to the verb (predicate), but you can't say it's simply an adverb (you can't use a te-form verb alone as an adverb). The word 付帯状況 literally means "collateral situation" (I wasn't able to find a proper English translation) that means what you're doing alongside doing action that is described with main verb, such as:

彼は時計を見てため息をついた。

→ Looking at the watch, he gave a sigh.
→ He looked at the watch, and gave a sigh.

The two translations are telling almost the same thing, but if you translate like the former one, it becomes an adverbial clause, while the latter looks more like serial verbs. Te-form can represent a wide range of relations between verbs, from almost independent two actions (酒を飲んで肉を食べる) to almost subordinate (包丁を使ってたまねぎを切る), depending on the context.

～を使って leans particularly to the subordinate side, as it always expects a verb that comes after it when it's used. Therefore, the phrase is usually translated as single words such as using or with.