What is the appropriate etiquette for sending a thank you email to a professor at the end of the semester?

When sending a thank you email to a professor at the end of the semester, it is important to be polite, concise, and specific about what you are grateful for. Address them respectfully, mention something specific you appreciated about their teaching or guidance, and express your gratitude for their help throughout the semester. Keep the email professional and considerate of their time.