The creature sat upright and tugged at the shackles binding his ankles, Frankenstein uttered a piercing scream.

How do you rewite a fused sentence

Fused sentences and comma splices are just variations of the same thing -- run-on sentences. Just be sure you put a period at the end of each sentence (or ? or ! if needed) and a capital at the beginning!

http://grammar.ccc.commnet.edu/grammar/runons.htm

That sounds like one sentence so how would I add a period

It's two sentences. Did you read the information at the link I sent?

The creature sat upright and tugged at the shackles binding his ankles

Frankenstein uttered a piercing scream


How will you make it clear that these are TWO sentences??

??

by adding a period behind ankles

Yes, that's the basic way.

You could also write When the creature sat upright and tugged at the shackles binding his ankles, Frankenstein uttered a piercing scream.

By adding "when" and making the first clause subordinate, the relationship between the two sentences is clearer and it doesn't sound so choppy.

=)

To rewrite the fused sentence, you can add a period behind "ankles" to separate the two sentences. The revised version would be:

"The creature sat upright and tugged at the shackles binding his ankles. Frankenstein uttered a piercing scream."

That's correct! Adding a period after "ankles" would separate the two sentences and make them clearer. Another way to rewrite the fused sentence is by adding a coordinating conjunction. For example, you could write, "The creature sat upright and tugged at the shackles binding his ankles, but Frankenstein uttered a piercing scream." The addition of "but" shows a contrast between the actions of the creature and Frankenstein. Remember, when rewriting fused sentences, the goal is to make the relationship between the two ideas clear and properly punctuate them.