Final answer:
The sentence 'That is how to make pie crust,' my grandmother said, is correctly punctuated and does not need additional commas. It demonstrates an accurate use of commas and quotations marks for direct speech in English grammar.
Step-by-step explanation:
The sentence 'That is how to make pie crust,' my grandmother said is correct and does not need any added commas. The sentence is an example of direct speech reporting, portraying a spoken dialogue by a character. In English grammar, direct speech is punctuated using quotation marks before and after the spoken words. A comma is used to separate the dialogue from the rest of the sentence and is placed before the quotation mark. In this sentence, all these requirements are met so no additional commas are necessary.
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