David Mitchell, Variations on a Theme by Mister Donut
It's the start of a new school year so a few weeks into the book, seven-year-old learners of English will soon be inquiring "Is this a pen?" But as the quotation above indicates, this is a question it's quite unlikely they'll be faced with in real life - most speakers of English recognize a pen when they see one and have no need to ask.
In fact, a quick search of the British National Corpus, returning 50 random results for the phrase "Is this" doesn't contain a single example of "Is this a [singular noun]?"
The most common types of question in the 50 examples are:
- five examples such as "How is this done?", with this used for anaphoric, not exophoric reference
- two examples of "Is this the ..." as in "Is this the start of a new series then?
- It is this state that fascinates particle physicists.