The English gerund is a verbal substantive and can therefore be used as an object or subject of a sentence.
Reading is fun. => Reading is the subject of this sentence.
I like reading a lot. => Reading a lot is the object of the sentence.
The Italian gerundio is not a verbal substantive and can never be used as an object or a subject. The English gerund, which is not to be confused with the English present participle, is to be traduced with an infinitivo who actually can be used as a verbal substantive.
Translate these sentences to English using an infinite form.
Reading books was the only thing one could do.
Reading these books he learned a lot.
Writing with a pen ball is an ability the next generation will not have any more.