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Can I say,

(a) The supermarket had a sale.

(b) The supermarket was crowded because had a sale.

(c) The supermarket is having a sale / is organising a sale.

(d) The supermarket is for sale / is having a big sale on / for clothes.
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(a) The supermarket had a sale.
(b) The supermarket was crowded because it was having a sale.
(c) The supermarket is having a sale.
(d) The supermarket is having a big sale on watermelons. Supermarkets do not sell clothes; department stores do. Also, supermarkets seldom have sales; department stores often do.
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Thanks, can I say,

The supermarket is on the sale / on sale.
No, of course not-- they are not selling the supermarket, are they? They are just selling the products it carries.