formed of molecules vs formed from molecules

A problem with preposition , I’m so embarrassed to read this sentence:
“No matter how complex,all matter is formed of molecules”
I wonder why they don’t use ‘‘FROM’’ or “BY” before FORMED.Please help me!
Thanks in advance!

You can also use “from” or “by”, and it makes no real difference in the meaning.

By the way, what does duc’s original sentence mean? How can molicules be made into matters? => I don’t understand!!! :open_mouth:

I don’t know too :D,it is a sentence in my book

Hi duc

First of all, I’d like to mention that your last sentence should be worded this way:
“I don’t know either.”

The word matter is used in two different ways in your sentence. I suppose the author of your sentence was trying to be clever or tricky. :?

The second usage of matter in your sentence is definition 1 here:
physical substance or material in general