Works : Islamic Laws
2105. It is not necessary that the formula of purchase and sale be pronounced in Arabic. For example, if the seller says in any language: "I have sold this property in exchange of this money", and the buyer says: "I accept it", the transaction is in order. However, it is necessary that the buyer and the seller should have Niyyat of Insha' - which means that by uttering the above mentioned words, they are genuinely intent upon buying and selling.
2106. If the formula is not uttered at the time of transaction, but the seller hands over to the buyer that which he owns, in exchange of the property which he takes from the buyer; the transaction is in order, and both of them become the owners.