Let's first explore what's the big deal about those thesis statements...

English as a Second Language English Vocabulary, Grammar and Idioms
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A lot of people have been asking me lately about writing a good thesis statement. And this is a great question I’ve been planning to write on for some time now. Let’s first explore [color=red]what’s the big deal about those thesis statements, and then dive in to see how to write them.

[color=red]what’s the big deal about those thesis statements
Isn’t “what the big deal about those thesis statements is” correct?

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Yes, it is.

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Thank you, Mordant.

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I would say either, “what the big deal is about thesis statements,” or, “what the big deal about thesis statements is”, as you wrote. In my opinion the author is being a bit too colloquial.

By the way “thesis” is a very troublesome word for people who don’t learn to pronounce “th”. Some of them replace “th” with an F sound, and they end up saying “feces statement”. I even heard a woman finishing her master’s degree say that she had to defend her “feces” in front of a committee.

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Thank you, Jamie.

I prefer your version, which is “what the big deal is about thesis statements.”