Использовать "а" где необходимо: What _ fine weather! What _ pretty mouse! What _ good news! What _ unpopular advise! What _ beautiful hair! What _ deep snow! What _ interesting books! What _ talented men! What _ important data! What _ smart woman! What _ nice guy

What _ fine weather! What a pretty mouse! What _ good news! What _ unpopular advise! What _ beautiful hair! What _ deep snow! What _ interesting books! What _ talented men! What an important data! What a smart woman! What a nice guy

What  fine weather

What a pretty mouse!

What good news!

What unpopular advise!

What beautiful hair.

What deep snow!

What interesting books!

What talented men!

What an important data

What a smart woman!

What a nice guy!