No, because you are not looking up the syntax, just making it up as you go along.
I know of someone else that does that and he has been using Access for almost 20 years. :-(
Look up the syntax and see if you can work it out yourself, or look at the Left function. The right and left has the same syntax, the Mid() is slightly different. Regardless, Google the syntax, that is the only way you will learn.
We all make mistakes, and LarryE has done so in this case, but you always need to understand any code supplied to you.