Hello Jaehee Lee: No, you will want to write it a little differently, as follows: "I went shopping yesterday. [okay] The shop which you usually go to was having a sale. They had a 50% discount."

"I went shopping yesterday" is just fine. Good work there. ;) When we talk about a store hosting a sale, we say that the store is "having" a sale. For example, "Macy's had a big sale last weekend for Black Friday." Or, more specifically, "Macy's has a sale on shoes today." If we are talking about an item being sold more inexpensively, then that item is "on sale". So, "I am going to buy those shoes, since they are on sale." In your example, I'd say "The shop where you used to go was having a sale." As for the discount, it'd be more common to say "Everything is 50% off." It is technically correct to say, "Everything is discounted by 50%", but this is awkward. Hope that helps!

Oh! Thank you so much! How did you find out!! Super!

Hi, there! And something less important yet needed is the word "it" which is missing from your question at the bottom. "Can I say IT like this/this way?" OR "Is THIS correct?" OR "Is IT/THIS a right way/expression?".

To elaborate, for the sake of clarity, you will want to consider the possible ways of expressing the ideas about the store sale. "The shop which you usually go to was having a sale" "Today, the shop you usually to go is having a sale. Everything is being sold at a 50% discount". "Tomorrow, the shop which you usually go to is having a sale. Everything will be discounted 50%"