externalia外生殖器externaladj.外来的；外部的；外面的；表面的n.外观；外部；外界事物external fan kiln外装风扇干燥窑external air loop外部空气external waviness表面波纹external fLxation外固定架external property外部性external receipts外来<海外；国外>收入external exposrue外(部)照射external engineer表面工程External fixatror外固定器external irritant外来刺激

1. Problems include water in the pipe and lack of clearance between inner and outer pipe walls.
   问题包括管中有水以及在内管和外管之间缺乏清洁。