●from ˈscratchwithout any previous preparation or knowledge
从零开始；从头开始◆The prototype was designed and built from scratch in just one month.
这个原型是在仅仅一个月之内从零开始设计制造出来的。●(be/come) up to ˈscratch ●(bring sb/sth) up to ˈscratchas good as sth/sb should be; satisfactory
合乎标准；达到要求◆His work simply isn't up to scratch.
他的工作简直不符合要求。◆Our products are good, but we need to bring our customer service up to scratch.
我们的产品很好，但我们必须使客户服务达标。