A) The best thing about the weekend is “not going” to work. (gerund) The reason you use a gerund here is you are referring to the verb (go) as a thing (object) and as such you are making the verb “go” function as a noun by adding -ing If you tried to use “not to go” in this sentence, as in “The best thing about the weekend is not to go to work” there is no thing (noun) that you are referring to.

"The best thing about the weekend is not having to go to work". A)not going = colloquial speech where it gets shortened B)not to go = incorrect you can rewrite the sentence as above to include not to go to X Wait for a component teacher to explain the gerund rules whys and reasons.

Either one. But gerund sounds more natural here, for some reason I cannot pin-point.

The best thing about the weekend is not going to work. In this case, the gerund verb "going" is a complement to the verb "is". It's a common use of the gerund in English - hopefully someone can help explain exactly why for you and provide better clarification. I hope I helped a little bit! :) Here are some other examples: -One of his duties is attending meetings. -The hardest thing about learning English is understanding the gerund. -One of life's pleasures is having breakfast in bed.