In comparison to other sign languages around the world, why is asl considered a sophisticated and mature form of sign
language?

It has its own structure, grammar, and word order.

Explanation:

Do the signs of American Sign Language (ASL) stand for English words? A simple test is to find English words that have two different meanings. If ASL signs stand for English words, there would be a sign with the same two meanings as the English word. For example, the English word "right" has two meanings: one is the opposite of "wrong," the other is the opposite of "left." But there is no ASL sign with these two meanings. They are expressed by two different signs in ASL, just as they are expressed by two different words in French, Spanish, Russian, Japanese, and most other languages.