letter of mart and countermart

例句：

1. 1. The letter of mart isa legal document that confirms ownership ofa piece of property.
   马特信是一份法律文件，确认了某件财产的所有权。
2. 2. The letter of countermart is a document that confirms thetransfer of ownership of a piece of property.
   对马特信是一份文件，确认了某件财产所有权的转移。
3. 3.Both letters are important for ensuring the propertransfer of ownership during a sale or purchase.
   这两种信件对于确保在销售或购买过程中所有权的正确转移都非常重要。