syntax - Issue with Haskell's "do" -

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I wrote a Haskell function that calculates the factorial of each number in a given list and prints on the screen is. 

  factPrint list = If put in the list of faucets, then the STRLN and STRN (show.fact.head) lists the factprint (tail list)

The function works, but the third line is a bit confusing. Why did the compiler (GHC) not report an error on this because there is no one before "putStrLn" (semi?) Function? If I leave "Do" from the 4th row, then an error arises as expected.

I am quite new and am new to its method, so please forgive me if I am saying something very silly. 

  do STRN (show.fact.head) list) factPrint (tail list)  / Code>  
 There is actually another way to write  
  putStrLn ((show.fact.head) list) & gt; & Gt;  
 
 which means, 
 
  putStrLn (list of show.fact.head))> gt; & Gt; = \ _ - & gt;  
 
 Without these other ugly syntax, there is a convenient way to string these monads together. 
 
 If you have only one statement inside  do , then you are not stringing anything together, and  do  is unnecessary.

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