Final answer:
The answer explains how to rewrite a sentence using 'it' as the introductory subject.
Explanation:
To solve a difficult problem can be challenging.
When written as an introductory subject, the sentence would be: It can be challenging to solve a difficult problem.
By restructuring the sentence to introduce 'it' as the subject, it becomes more direct and engaging for the reader.
Learn more about Sentence restructuring here:
https://brainly.com/question/39281045
