Just wondering if someone could double check my work and verify it's ok? I'm coming up with a few errors, any help is appreciated - thank you!

Create a form allowing a user to enter a paragraph of text into a single textarea and click submit. Upon submission, output some statistics including:

The number of sentences

The number of words

The number of characters

The numbers of words that start with a vowel

Lastly, look up a string modifier to remove all punctuation and then output every word in alphabetical order.

My code so far is below, any help is appreciated.

html> lang="en">  charset="UTF-8">  rel="stylesheet" href="style.css">   
id="form1" name="form1" method="post"> 
Enter some words below, this should: 
 class="list"> 
 
List the number of sentences
 
Display the word count
 
Display the number of characters
 
List the number of words that start with a vowel
 
  
Lastly, lookup a string modifier to remove all puncuation and then output every word in alphabetical order.
  
 type="submit" name="submit" id="submit" value="submit"> 
 
 
 if (function_exists('word_count')){ function word_count($str, $n = "()"){ $m = strlen($str) / 2; $a = 1; while($a < $m) { $str = str_replace("","", $str); $a++; } $b = explode("", $str); $i = 0; foreach ($b as $u) { $i++; } if($n == 1) return $b; else return $i; } } $str = "Hello php world!"; $c = word_count($str, 1); //if return array $d = word_count($str); //if return how many words in text area print_r($c); echo $d; ?>  
Results
 
 
Number of sentences: $m; ?>
  
Word count: $b; ?>
  
Number of chatacters: $i; ?>
  
Number of words that start with a vowel: $a; ?>