When I was studying grammar, I learned that when we want to use a verb in its 'infinitive form' at the beginning of a sentence, we must use it in its 'gerund form', otherwise, if I used 'to' at the beginning of the sentence the verb wouldn't be in its 'infinitive form' because 'to' would be a preposition. I'm gonna give an example for you guys to understand better what I mean.

"Reading a little bit every day is an awesome activity". (Even though the verb is in the 'gerund', it means 'infinitive'.) [ Is this correct? ]

"To read a little bit every day is an awesome activity". (the word 'to' in this sentence doesn't put the verb 'read' in its 'infinitive form' because 'to' works as a preposition in this case.) [ Is this correct? ]

So, my question is: Must I always put the verb in its 'gerund form' to mean 'infinitive' at the beginning of a sentence or can I use both forms meaning the same? And is there any grammar rule which explains that?

  • 1
    The 'to' in a to-infinitive is a distant relative of the preposition 'to'. Try putting any other preposition in acceptable sentences like 'I like to hike', 'Is it all right to sit here?' 'To travel is better than to arrive.' The last sentence could be equally grammatically (but less punchily) recast as 'Travelling is better than arriving.' I'll close-vote when I find a thread where sentences starting with a to-infinitive are compared / contrasted with those starting with an ing-form; there was one very recently. Apr 23, 2020 at 14:00
  • 4
    Does this answer your question? "Being" or "to be"? Actually, gerund versus infinitive is a closer match, but was closed as a duplicate of this. John Lawler's answer here adds further advice hereabouts. Apr 23, 2020 at 14:04
  • To read a little bit every day is to start a sentence with an infinitive, not a preposition. If it helps you, pretend there are four sound-alike words: Two, Too, To (preposition), and To (infinitive marker). Apr 23, 2020 at 15:14
  • What you learned in school was wrong. Not terribly wrong, but far from complete. It is true that gerunds are more common than infinitives as subjects, but there are reasons for this. However, the stuff about to is totally wrong. You have to use to when an infinitive is subject, because to marks it as a subordinate clause; otherwise you couldn't parse it correctly. That makes infinitives awkward as subjects, but not ungrammatical. Apr 23, 2020 at 15:23
  • Break it and you buy it! That's perfectly acceptable in informal grammar (which is a legitimate form of grammar), and probably how somebody giving a verbal warning to somebody else would often phrase it. Other examples are Say it isn't so! and Duck! Apr 23, 2020 at 15:55