Used to add an extra point or reason, especially one that strengthens an argument already made.
“It's cheaper and closer to work, not to mention it has free parking too.”
“The new laptop is faster, not to mention the battery lasts almost twice as long.”
This is a handy phrase for stacking a second or third reason onto your main argument in Task 5, helping you extend your response naturally when you need to fill the full response time. Use it to add a smaller supporting detail after your main point, rather than opening with it.
Synonyms: not to speak of, plus, on top of that