When the price of purchased goods exceeds 100 yuan, 50 yuan will be deducted, that is, when the price of purchased goods exceeds 100 yuan, 50 yuan will be deducted. For example, the cost of goods is 120 yuan, and what is actually paid to the salesperson is 120-50 = 70 yuan;

If it is returned to 50 yuan at the price of 100 yuan, the purchased goods will be returned to 50 yuan at the price of 100 yuan. For example, if you spend 120 yuan on shopping, the salesperson will return them to you in 50 yuan.

Buy 4 bottles and get 1 bottle. If you buy 4 bottles of drinks, the salesman will give you 1 bottle.