求翻译：甲方如对产品安装工程提出变更时，应在乙方施工前提出，否则应承担必要的返工及材料费用和延误工期的责任，如对产品型号、尺寸改变，应在下料之前，否则一切责任由甲方承担。是什么意思？

Party, such as the installation of the product proposed changes should be made before construction B, or should bear the necessary rework and material costs and delays in schedule of responsibilities, such as product type, size change, should be before the next feeding, otherwise all the responsibil

A Party shall, if the product installation works in a time of change, Party B shall be made before construction, otherwise it should assume the necessary 264,165 2006/4 and material costs and delays, such as the responsibility of product type, size, and should be changed, otherwise, all before next

The party of the first part like the installation work to the product to propose when change before, should construct in the second party proposed, otherwise should undertake essential doing over and the material expense and the delay time limit for a project responsibility, like to the product mode

Party a if the product installation so changes should be made before the construction of party b, you should take the necessary responsibility of rework and materials costs and missed deadlines, such as on the product model, the size changes should be before the next, otherwise all the responsibilit

Party a if the product installation so changes should be made before the construction of party b, you should take the necessary responsibility of rework and materials costs and missed deadlines, such as on the product model, the size changes should be before the next, otherwise all the responsibilit