The best crossword in history

This is a puzzle created by Lee sallows. The following crossword contains 6 horizontal phrases and 6 vertical phrases. Each phrase is in the form of "how many XX letters", such as "Thirteen ns" and "Eight es". It indicates that the entire crossword contains exactly 13 letters N, 8 letters E. Because the entire crossword contains 12 phrases, this means that the crossword solution contains only 12 different letters. Niu B is Niu B, and this crossword has a unique solution. Can you find this solution?

 
A breakthrough is a vertical phrase with only five letters in the middle column. It can only be "one ?" . At the bottom, the horizontal phrase containing six letters can only be "Two? S "," Six? S and ten? S ". However, filling in "two" and "Ten" is impossible, otherwise there will be more than one letter O and N. Therefore, the six letters can only be "Six? S ". The longest column can only be "Thirteen SS", "Fourteen SS", and "Eighteen SS", but "Fourteen" is impossible, because there is no number of words with the F header length of 5. "Eighteen SS" is also impossible, because even if the "seven" may appear, 12 phrases are not enough to generate 18 s. Therefore, the longest column can only be "Thirteen SS ". Only "three" is a number of words with a T head length of 5, and only "four" is a number word with a 4 length ending with "R ". Now, we have determined the location of 12 s, but there is another S, and the places where "six", "Sixteen", and "Seventeen" are missing, therefore, one of the two shadow words must be "seven ".

 
The column not filled in the middle can only be "four? S "," Five? S "," nine? "S", but "Nine" is impossible, otherwise there will be more than three letters "N. Therefore, "Seven" is not in the horizontal shadow position. Otherwise, there will be more than four or five E numbers. Then "seven" can only be in the vertical shadow position. At this point, we have determined that the 12 letters in crossword are efhinorstuvx and there is no letter G. Therefore, the horizontal shadow is not "Eight", but "three ". Compare the number of existing letters with the number of unfilled phrases, and the remaining spaces will soon be completed. The following is the unique solution of this crossword: