title: Create column containing a list of words (unique) used in the sentences that appear in another column?
body: <p>In my Google Sheets I have a column with sentences (one per row) like:</p>
  
  <pre><code>How is it going?
  I am going to the store.
  He is going to play baseball.
  </code></pre>
  
  <p>I want to create another column that would contain a unique list of words (one word per row, ignoring capitalization as if everything were lowercase), so a few rows of it might look like:</p>
  
  <pre><code>how
  is
  it
  going
  I
  am
  to
  the
  store
  </code></pre>
  
  <p>etc.</p>
  
  <hr>
  
  <p>Also, as a bonus, I am looking to create ANOTHER column that would have the amount each of these words appeared. For example, it the first few rows might look like:</p>
  
  <pre><code>1
  1
  1
  2
  </code></pre>
  
  <p>because <code>how</code>, <code>is</code>, and <code>it</code> appear once and <code>going</code> appears twice.</p>