关键词法定解除条件 根本违反 预期违反Abstract The legal right to terminate (avoid) contracts is a remedy for breach of contract provided by laws available by the non-breaching party when it suffers great losses due to the breach. This remedy leads to the termination (avoidance) of the contracts of parties, so all countries provide very strict limitative requirements for it but they are quite different in specific provisions. This thesis will compare and analyze those relative provisions in contract laws