A learner sentence can be grammatically understandable but still sound stiff, translated, or incomplete.
A sentence can follow basic grammar and still sound like it was translated word-for-word. Natural Chinese depends on word order, collocation, omitted information, and the level of formality.
Correct does not always mean natural
For example, a grammar checker should fix clear errors first. Style suggestions should be treated as optional unless the original sentence blocks understanding.
Separate errors from suggestions
Strict grammar errors include wrong measure words, confusing word order, missing sentence parts, and incorrect use of 了, 过, or 着.
Naturalness suggestions are different. They may make a sentence smoother, but they should not invent facts or change the writer's meaning.
Use feedback actively
When you receive a correction, compare the original and corrected version. Ask what changed: the word, the order, the grammar marker, or the tone.
This habit turns each correction into a reusable rule instead of a one-time fix.