Do I need parentheses or dashes in this sentence?

Copernicus as you might know. decided that the earth travels around the sun.

You need commas after Copernicus and after know.

I would use commas to set off, "as you might know,"

My on,y choices are dashes and parentheses....

Dashes show an abrupt break in thought

Parentheses set off material loosely related.

Both Ms. Sue and Reed are correct. Only commas are needed in this sentence. There's a problem with your text and/or the question.

In this sentence, you have written "as you might know" as an interrupting phrase. You have two options to indicate this interruption: parentheses or dashes.

To decide between parentheses or dashes, you can consider the emphasis and the level of interruption you want to convey.

1. Parentheses: If you want to make the interruption less prominent and more secondary to the main sentence, you can use parentheses. It indicates a quieter interruption or additional information that is not critical to the main idea. For example:

- Copernicus (as you might know) decided that the earth travels around the sun.

2. Dashes: If you want to make the interruption more prominent and give it more emphasis, you can use dashes. It indicates a stronger interruption that demands attention. For example:

- Copernicus — as you might know — decided that the earth travels around the sun.

Ultimately, the choice between parentheses or dashes depends on your writing style and the effect you want to achieve.