31. which sentence uses commas correctly?
tick one.
realising, she had forgotten her purse sandie had to
go back home,
realising she had forgotten her purse, sandie had to
go back home.
realising she had forgotten her purse sandie, had to
go back home,

Realizing she had forgotten her purse, Sandie had to  go back home.

Explanation:

Because you can't add comma at the end of the sentence and the other this you can't add comma after realizing because it's not coordinating conjunction (and, but, for, or, nor, so, yet) that links two independent clauses.

The second one is the correct answer because they are two dependent clause. Use a comma after a dependent clause that starts a sentence.