1. Jeans are on sale, 30 % off today!

2. Jeans are 30% off today!
3. Jeans are for sale, 30 % off today!
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Are both the same in meaning? Can we erase 'on sale'? Can we say #3? What is the difference between #1 and #3?

'on sale' means that the jeans are on discount, while 'for sale' means that you are selling jeans.

2. is possible.
For 3, 'are' is omitted in this kind of usage, so 'Jeans for sale, 30% off today!' Forms of 'be' are often used in informing, such as telling someone "These jeans are for sale" or in 1.

Hope this helps!

All mean about the same thing, yes.

1. Jeans are on sale, 30% off today!

2. Jeans are 30% off today!
3. Jeans are for sale, 30% off today!

All three sentences convey the same meaning and indicate that jeans are being offered at a discount of 30% specifically for today. However, there are slight differences in wording and emphasis.

1. "Jeans are on sale, 30% off today!" - This sentence explicitly states that the jeans are on sale, highlighting the fact that the discount is available for a limited time only. The phrase "on sale" emphasizes the special nature of the discount.

2. "Jeans are 30% off today!" - This sentence directly states the discount, without mentioning that the jeans are on sale. While the concept of a sale is assumed, it is not explicitly mentioned. This sentence is more straightforward and focuses solely on the discount percentage.

3. "Jeans are for sale, 30% off today!" - This sentence combines the idea of the jeans being both "on sale" and "for sale." While it may be technically correct, it is less common to use the phrase "for sale" in this context. "For sale" is typically used to indicate that an item is available for purchase, without necessarily implying a discount.

In summary, all three sentences are similar in meaning but differ slightly in wording and emphasis. Sentence 1 emphasizes the limited-time nature of the discount, sentence 2 is a straightforward statement of the discount, and sentence 3 combines the idea of being on sale with the discount.