单项选择题
A.Constant inspection B.Keeping constant load C.Remaining constant temperature D.varying speed
（） are mounted on and bolted to the bed-plate cross gir...
单项选择题（） are mounted on and bolted to the bed-plate cross girders.
A.The crankshaft B.The crankcase C.The guide-ways D.The frames
（） are formed by abrasive particles entering the bearin...
单项选择题（） are formed by abrasive particles entering the bearing and scoring the shaft.
A.Grooves B.Recesses C.Ridges D.Nips
（） are fitted in the exhaust system and facilitate char...
单项选择题（） are fitted in the exhaust system and facilitate charge removal and scavenging in each cylinder.
A.Diffusers B.Compressors C.Steam boilers D.Soot blowers
