Thank you very much David for your wonderful explanation.
David, Moderator postedsymphony posted:
The verb after ‘have to’ is used in base form only, right?
No. As you can see, having to is also used, both as a present participle and as a gerund. Have to also has the past-tense and past-participle form had to (He had to / has had to help out a lot) and the third-person singular present formhas to.
I mean the verb used after have to should be in the base form.
For eg: have to + verb (base form)
have to + work