YJ17卷烟机喇叭嘴上面的（）使两个喇叭嘴安装位置不会混淆。
参考答案：导槽
肺癌的主要临床表现是咯血（）
There（）in that part of the country.
A．are not much industry
B．is not many industry
C．are not many industry
D．is not much industry
