When I write about gerunds and infinitives, I usually use examples that contain one gerund or infinitive.
Running is good exercise.
To run was my choice.
However, both gerunds and infinitives can be used with adverbs in prepositional phrases or as objects.
Gerund: Running slowly is the best can do.
Infinitive: To run slowly will be easier for me.
With prepositional phrases:
Gerund: Running in a race is fun for many people.
Infinitive: To run in a race is better than to sit in front of the tv.
In the textbook, Grammar Sense 3, Susan Kesner Bland points out that although we can use an infinitive as a subject, it not common. Usually, the infinitive is replaced by it as the subject and the infinitive occurs later in the sentence.
It is easier for me to run slowly.
She further points out that only a few verbs are used after it.They are:
Usually the infinitive is not used immediately after these verbs, but it can be done.