A. If either John or Gary fails to bring their power drill, we will not complete this job on time, which our boss will consider unacceptable.
It's a verb that has to have a ACTION and a SUBJECT is the sentence.
Answer:
There is no way to say rather or not someone will regret a life choice, later on, even if don't regret it after making the decision. But one way is before doing anything, is to think it through. For how every long it takes. Ask yourself, "Is this really best for me?", "How will this choice affect others around me?", "Is this really helpful in the long run"?. Asking questions like these, may just help come to a decision. If you decided this is certain choice is the BEST for you. Then you should go for it. While you can't be promised you won't come to regret the decision, it you feel good about it and have thought about long-term consequences you should do what feels best.
