Give the email a subject that identifies the task: "Request for the revised class timetable." A subject such as "Question" makes the reader open the message before discovering what it concerns.
A practice message could read: "Hello Maya, I am arranging my work shifts for next month. Could you send me the revised evening-class timetable? If it is not ready yet, please let me know when you expect to publish it. Thank you, Luis."
Explain a deadline when one exists
If you genuinely need an answer by a particular time, state it and explain why: "I need to submit my shift choices by Thursday afternoon." This gives context without pretending that your deadline automatically creates an obligation for the recipient.
Check whether you have asked several unrelated questions. Separate them clearly when all are necessary, or send a focused message for the immediate decision. Avoid burying the request after a long account of previous conversations.
Revise the example for a familiar classmate and then for an unfamiliar course administrator. The greeting and degree of formality may change, while the task should remain clear. Before sending a real email, verify the recipient, attachment references, and dates. Read only the subject and the request sentence: together, they should tell the reader what you need and why a response is useful.