on offer

Từ điển Oxford Advanced Learner 8th

on ˈoffer idiom
1. that can be bought, used, etc
•The following is a list of courses currently on offer.
•Prizes worth more than £20 000 are on offer.
2. (especially BrE)on sale at a lower price than normal for a short period of time
•Italian wines are on (special) offer this week.
Main entry: ↑offer_idiom