This contract is made in two originals that should be held by each party.   
此合同一式二份，由双方各持一正本。 
What is left unmentioned in contract may be added there as an appendix.     
本合同未尽事宜，可由双方增补作为合同附件。

The Contract is written in quadruplicate (two for original and copy respectively) which shall become valid on the date of signature.     
本合同一式四份（正副本各两份）自签署后生效

This Contract is executed in two counterparts each in Chinese and English, each of which shall be deemed equally 
authentic. This contract is in 2 copies effective since being signed/sealed by both parties.  
本合同为中英文两种文本，两种文本具有同等效力。本合同一式两份。自双方签字（盖章）之日起生效。

This contract is made by and between the buyers and sellers， whereby the buyers agree to buy and the sellers agree to sell the under-mentioned. Commodities according to the terms and conditions stipulated below.     
本合同由买卖双方签订，根据本合同条款，买方同意购买，卖方同意出售以下产品。
买方 buyer  
卖方 seller