To punctuate this sentence correctly, follow these guidelines:
1. Use quotation marks: As the title of the article, "Increase Your Vocabulary" is written within double quotation marks.
2. Add a comma after "entitled": After the word "entitled," insert a comma. This separates the introductory phrase from the main part of the sentence.
3. Formatting the title: In terms of how to format the title, it depends on the style guide you are following. However, some commonly accepted practices include italicizing or using quotation marks. If you are using quotation marks, as shown in the sentence, you don't need to underline the title.
So, to correctly punctuate and format the sentence, it should read:
"Have you read the article entitled, 'Increase Your Vocabulary'?"