Tube to... 地铁开往tuben.管子；管状物；<英>地铁；电视；管状器官v.提供或装上管子tube rolling aircrew轧管机组tube offset position偏移量tube forming segment成管段tube-sheet welding管-板焊机tube truss structure管桁架结构tube wall thickening管壁增厚tube bending machine弯管机tube sheet structure管板结构tube push-out tool管推出工具tube heating furnace管式加热炉

1. The tube nucleus disintegrates as the pollen tube penetrates the nucellus.
   另外的粉管核会在花粉管穿过珠心时发生分裂。