求翻译：在签订本合同之前，买卖双方当事人可要求对方出示身份证明、企业法人营业执照、房地产证等有关证明文件，并认真审阅合同内容，仔细确认其中的选择性、补充性、修改性内容。对合同条款有疑问时，可向法律人士咨询。是什么意思？

Prior to the signing of this contract, the parties may require the buyer and seller proof of identity, business license, real estate license and other relevant documents, and carefully review the contract carefully to confirm the selectivity of which supplement, modify content. Doubt on the terms of

Before the execution of this Contract, the Purchaser and the seller may ask proof of identity, business license, etc. , real estate license and reviewed carefully the required documents, contracts, and carefully confirmed that among the selective content, complementary, modify sexual content. there

In signs in front of this contract, the round turn litigants may request opposite party to show the identification, the business entity business license, the real estate card and so on the related proof document, and scrutinizes the contract content earnestly, confirms selectivity, supplemental, the

Prior to the signing of this contract, the seller and the party may request proof of identity, business license, certificate, and other relevant certificates, and to carefully review the contract content, carefully to confirm which of selectivity, Supplement, modify the content. On the terms of the

Prior to the signing of this contract, the seller and the party may request proof of identity, business license, certificate, and other relevant certificates, and to carefully review the contract content, carefully to confirm which of selectivity, Supplement, modify the content. When you have questi