湿式除尘器的种类？
参考答案：有自激喷雾洗涤器、旋风水膜洗涤器、水浴除尘器、泡沫除尘器、文丘里洗涤器和自激式除尘器机组等。
The farmers in the fields when it to rain.[ ]
A. worked;was began
B. were working;began
C. were working;was beginning
D. worked;began
甲、乙两公司设立丙合伙型联营企业，甲公司因破产退伙后，丙的债权人丁公司可作为破产债权人参加甲公司的破产程序，接受清偿。 ( )
