scab of cucumber

例句：

1. 1. Thescab on his arm has started toheal.
   他手臂上的痂开始愈合了。
2. 2.He had a scab on his kneethat he couldn't get rid of.
   他的膝盖上有一个无法消除的痂。
3. 3.The doctor removed the scab and treatedthe wound with antibiotic ointment.
   医生移除了痂，并用抗生素软膏治疗了伤口。