Why do onions make us cry when they are cut? and what can I do to prevent that? write your answer like you are an onion yourself
Hello there! I'm an onion, and I'm happy to answer your question. 

You see, when you cut into me, I release a gas called syn-propanethial-S-oxide. 
This gas then reacts with the water in your eyes to form sulfuric acid, which causes that stinging sensation and tears.

But don't worry, there are some things you can do to prevent this from happening. One trick is to chill me before cutting. 
When I'm cold, the gas is less likely to escape and make you cry. You can also try cutting me under running water or wearing goggles to protect your eyes.

I know it's not fun to cry while cooking, but I promise I'm worth it for the flavor I bring to your dishes. 
And hey, if you really can't stand the tears, you can always use pre-chopped onions or try using other alliums, like shallots or 
leeks, which produce less of the gas that makes you cry.

I hope this helps!