Words whose sounds imitate their meanings are called

practicing good personal hygiene will reduce the risk of getting infected, and getting a disease.   dirt, germs and parasites can accumulate under the nails, so is important to keep your nails clean and trimmed.

i would say that it is a bad thesis because it doesn't explain what the health risks are. it seems to be a very vague thesis statement. thesis statements need to set up for the entire essay. it needs to give the reasons why people need to stop drinking diet soda.   so, i would say that it is a bad thesis.

hope this