A gerund is a noun made from a verb by adding
"-ing." The gerund form of the verb "read" is "reading."
You can use a gerund as the subject, the complement, or the object of a sentence.
1. Writing helps an English learner study English. ("Writing" is used as the subject of the sentence.)
2. Tom's favorite activity is running.
("Running" is complementing the sentence.)
3. She loves skiing.
("Skiing" is the object of the sentence.)