blotch
n
large discoloured mark, usu irregular in shape (on skin, paper, material, etc) (皮肤、纸张、材料等上的)大斑点
His face was covered in ugly red blotches. 他脸上有许多难看的红色大斑点.
When a student recently saw two workmen using a pneumatic drill outside his university, he immediately telephoned the police and informed them that two students dressed up as workmen were tearing up the road with a pneumatic drill.