Corrected sentence (best):
While the city sleeps, workers sweep, pick up trash, and fix cracks so the city looks nice by morning.
Other good options:
- While the city sleeps, they sweep, pick up trash, and fix cracks so the city looks nice by morning.
- While the city sleeps, workers sweep, pick up trash, and fix cracks. The city looks nice by morning.
Why this is better (easy steps):
- "These" needs a noun after it (these what?). Using "workers" or "they" tells who is doing the work.
- Start with the short phrase "While the city sleeps," — that is a dependent clause, so we keep the comma after it.
- Use commas between the list items: "sweep, pick up trash, and fix cracks." The comma before "and" (the Oxford comma) makes the list clearer.
- It’s clearer to join the ideas into one sentence so the reason is shown: they work at night so the city looks nice by morning.
Short tip: replace unclear words like "these" with a noun (workers) or a pronoun (they), and make sure your commas show the list and the pause after the opening phrase.