fettling magnesite grain

例句：

1. 1. Theold coat needed some fettling tokeep it in shape.
   这件旧外套需要一些修补才能保持形状。
2. 2. Afterthe storm, the roofof the house needed fettling.
   暴风雨过后，房子的屋顶需要修补。
3. 3. The car's engine neededfettling to fix the leakyvalve.
   汽车发动机需要修补来修理漏气的阀门。