<p>What is the difference between "of when" and "when" ?</p>
<p>Can you give an example of a usage of “of when” that you’re referring to?</p>
<p>silverturtle, I think it’s just a question of when Lovetheself will reply to your question. :)</p>
<p>A period of when
Or a period when? What is the difference between those two sentences, thanks.</p>
<p>Well, silverturtle is the true grammar expert, but I cannot think of a sentence that involves the phrase “a period of when” and is grammatically correct.</p>
<p>What is the difference between “of when” and “when” here? I have another question:
- significant factors to include in the budget when (buying) a car are the costs of fuel and maintenance and the insurance payments.</p>
<p>2) Ms. Kovan proudly displayed her research group’s most ingenious invention, a vacuum cleaner that emptied its own dust bag when (pressing a button).</p>
<p>1) why is when buying correct in the first sentence and when pressing a button wrong at the second sentence? Please help me guys i am entering may 2013 sat exam and i am really nervous</p>
<p>When a sentence includes a form such as “buying” or “pressing,” the action of buying or pressing needs an antecedent in the sentence who actually does the buying or pressing.</p>
<p>The second example (Ms. Kovan) is a bit easier to explain than the first. In the second case, the “vacuum cleaner that emptied its own dust bag” has been introduced just ahead of “when pressing a button.” Technically, this would mean that the vacuum cleaner is pressing the button. So that is not correct.</p>
<p>In the first example, you might make the same argument, to conclude that the budget is erroneously being said to buy the car.</p>
<p>However, there are correct English sentences that rely on words that are in effect “supplied mentally by the reader.” The first sentence can be understood as a kind of short-hand version of "Significant factors [for one] to include in the budget when [one is] buying a car are . . . Linking verbs (forms of “to be” and some others) may sometimes be correctly omitted, along with pronouns. It is rather tricky to decide whether a sentence with such omissions is correct or not. In this particular case, I would say that the use of “to include” implies a subject who is doing the including, and the same subject is buying the car. That differentiates it from the vacuum cleaner example.</p>
<p>I imagine that silverturtle can give you the technical terms for this. In any event, there is no need to be nervous. I think that the “significant factors” question is one of the harder ones. If you understand why the sentence about the vacuum cleaner is not right [and follow that logic throughout], you might miss a question, but you should do quite well overall.</p>