title: Counting the number of 7 character words in a file that start with tree and do not end in u or v
body: <p>I'm trying to count the number of 7 character words in a file that start with tree and do not end in u or v. I know how to specify the begin with tree and end in u or v condition in cat, but I'm not sure how to identify exactly 7 words or enter the conditions using wc. My pathname is /users/file1.txt.</p>
  
  <p>This is the valid cat command(missing number of 7 character words)</p>
  
  <pre><code>  cat /users/file1.txt | grep ^tree.*[!uv]
  </code></pre>
  
  <p>Below is the invalid wc command(missing number of 7 character words)</p>
  
  <pre><code>  wc - w /users/file1.txt | grep ^tree.*[!uv]
  </code></pre>