Burden means that something is a problem for you, like "Carrying this heavy bag is such a burden" Pressure is used in a few different ways. For example, "I am under a lot of pressure at work" means that they need to get something done in a quick and efficient way. Or, if you have a painful pimple on your face that means that there is a lot of pressure under the skin. Stress is also used in multiple ways. You could say "I am stressed because I have a lot of homework and projects due for school tomorrow" and it means that you are worried about it. You could also say "I cannot stress enough how important it is that you pick me up from school on time" it means that they can't say more about how important something is. I hope this helps you!

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