发动机气门的二种型式是:进气口和排气口.The two types of engine valves are intake and exhaust.同时,外面空气由进气口吸入代替被排出的空气.At the same time air is sucked into the inlet to replace the exhausted air.两侧进气口的水平烤架并纳入令人印象深刻的雾灯.Both side inlets have hori...
Minute fragments of shoot apices are proverbially difficult to culture.微小的茎尖切段通常是难以培养的.This concept has now been replaced, for stem apices, by the tunica - corpus theory.此观点目前已经被原套原体学说所取代....