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downdraft的音標：downdraft的英式發(fā)音音標為：['da?ndrɑ:ft]downdraft的美式發(fā)音音標為：['da?n?drɑft]...

n.倒灌風，下向通風，向下氣流...

倒焰...

downdraf的音標：downdraf的英式發(fā)音音標為：['da?ndrɑ:f]downdraf的美式發(fā)音音標為：['da?ndrɑf]...

Ventilation: positive downdraft exhaust ventilation should be provided to maintain vapor concentration below TLV.通風: 為了使氣體聚集程度維持在閥極限值之下,應(yīng)提供通暢的向下棋流排氣通風設(shè)施.Beijing Cherokee engine uses Cart YFA carburetor which is single ba...