<p>I always get confused when it comes to these 2 types of grammar rules. Please help! :)</p>
<p>ex) The book has received more praise than has its movie counterpart.
That wolf has a longer tail than has the chipmunk. </p>
<p>When do you compare with has... than has? Can you just say "The book has received more praise than its movie counterpart" or is that improper grammar? </p>
<ol>
<li>They display an interest in and commitment to the project. </li>
</ol>
<p>Why can't it be "they display an interest and commitment to the project" ?
or in the case of "They are both interested in and committed to the project", why do you need the "in"? I've seen other examples where its okay to combine the verbs like lets say, "They both ate and drank at the diner" where you didnt need to put anything after "Ate".
Is it because they're idioms? If they are idioms do you always put the corresponding preposition for each verb and if they're not do you just simply combine the verbs?</p>
<p>I don’t know on your first example, I would think your example is correct.</p>
<p>Your second example has to do with parallel construction.</p>
<pre><code>Interest in (the project)
Commitment to ( the project)
</code></pre>
<p>You need the preposition because you would not say interest the project or interest to the project.</p>
<p>‘Than has’ strikes me as an archaic or very formal construction. In most cases I would think it falls into the highly punctilious tone characteristic of coronations, academic papers and other places where sentences don’t end in prepositions and infinitives are not split.</p>
<p>It seems to perhaps occasionally serve a function to help make potentially ambiguous comparisons clear, as in : “The wolf has a longer tail than a chipmunk.” A tail longer than a chipmunk? or longer than a chipmunk’s tail?</p>
<p>On Wood5440’s chipmunk example, the sentence could also be written using the possessive: “A wolf’s tail is longer than a chipmunk’s.” This is just better writing.</p>
<p>MD Mom is exactly right about the second example. You could also say “They are interested in and committed to the project.”</p>