例句與造句

1. welding or rust surface etc . b . sharp-pointed objects c . steel cable d . heat source, eg exhaust pipies, sparks, burning stoves or heating apparatus etc
   b、尖銳物體c、鋼纜d、熱源體，如排氣管、火星、燃燒爐或加熱器等
2. It's difficult to find rust surface in a sentence. 用rust surface造句挺難的