Here's why:
* Subject: "She" is the subject of the clause.
* Verb: "Can" is the verb, but it needs more information to be a complete sentence.
* Meaning: The clause tells us *why* someone is doing something.
Example:
* So she can take a subject. (Incomplete sentence)
* She went to the library so she can take a subject. (Complete sentence)
In this complete sentence:
* "She" is the subject of the main clause.
* "Went" is the verb of the main clause.
* "So she can take a subject" is the adverbial clause explaining the reason for going to the library.
Therefore, the phrase "so she can" cannot take a subject or predicate on its own. It functions as a dependent clause, modifying a verb in a larger sentence.