If you hit check it and an error screen came up then there was an error for sure...If you think that you had it right and possibly the program was wrong...well that almost never happens...First thing to do is check for words like "could/would...they/them...and/any" in other words similar words where only one letter can make a difference.
If you are intent on trying to keep at a 100% solve rate then its a matter of trial and error and can take sometimes a long time to find the right answer which is very frustrating.
There is no way to see the actual solved puzzle unless you solve it...it will appear again at some point and you will have another shot at it.
If you are stuck and the author is listed you can try and google the author's name and match the letter pattern to some of their quotes.
This being a cheat is a greatly debated subject here but alot of us do it.
Otherwise, if you are not concerned at keeping a 100% solve rate, move on to the next puzzle...the puzzle you were working on will come up again in the rotation.
Hope that helps...you can also go to the chat box and enter the puzzle in there which requires alot of typing and time but someone will try to help you.
Welcome to the site!!!
Good Luck and Keep at it