There was no drugs > There were no drugs
"it would kill a person within a few days, or cause significant damage in their brains"
It's okay to use "their" when you don't know the gender of the person, but you cannot use "brains" when there is just one person.
‘Barefeet doctor’.
You can use either "barefoot" or "barefooted." No need to coin your own word.
"Little Grass sat outside the front door of her house and immersed in a worn-out fairy tale book."
I corrected your previous use of "immersing" to "immerse" based on your original sentence structure. If you changed your sentence structure like this, you cannot use "immersed" here. It would mean something different. The verb "immerse" in the meaning you want to use, needs to be used as in phrases like "be immersed in..." or "immerse oneself in..." So if you do want to make a correction, please follow my previous correction: "Little Grass sat outside the front door of her house, immersed in a worn-out fairy tale book."
It was a beautiful summer night! Splendid stars scattered in the dark blue sky.
It is the same case here. As I said in my previous post, the problem is that stars do not perform the action of scattering. That is why I changed the original sentence to "It was a beautiful summer night with splendid stars scattered in the dark blue sky." Now you have split the original sentences into two sentences. The second sentence would sound very awkward for the reason I mentioned earlier.
Finally, I would make a useful suggestion to you that you should turn on your auto speller in your computer. It may detect quite a few of those very obvious errors you seem prone to.
Also, please do not use too many exclamation points in your essay unless they are well justified as exclamation points are not as frequently used in English as in Chinese.
