Final answer:
Global revision involves overall structural changes, while local revision focuses on grammatical and stylistic improvements at the sentence level.
Step-by-step explanation:
Global revision refers to making changes to the overall structure and organization of a piece of writing, while local revision focuses on making grammatical and stylistic improvements at the sentence level.
For example, during global revision, you might rearrange paragraphs, add or delete sections, or rework the overall flow of the essay to strengthen coherence. On the other hand, during local revision, you might check for grammar, punctuation, and capitalization errors, and make corrections.
So, while global revision involves big-picture changes, local revision deals with fine-tuning the details to improve clarity and readability.