Questions: Consider the commas in bold, which are used to separate the items in a list. If they are not used correctly, remove them or replace them with different punctuation marks.

The commas in the sentence are used correctly to separate the items in a list. Therefore, no changes are necessary. Here is the sentence with the commas highlighted for clarity:

The Fujita Scale is used to measure the strength of tornadoes in Canada, the United States, the nations of continental Europe, and many other countries around the world.

Explanation:

• The commas are correctly placed to separate the different regions where the Fujita Scale is used.
• Each comma helps to clearly distinguish between the items in the list, making the sentence easier to read and understand.