通风

airy / ventilation / to ventilate / to disclose information

to go through / to know well / (suffix) expert / to connect / to communicate / open / to clear / classifier for letters, telegrams, phone calls etc

classifier for an activity, taken in its entirety (tirade of abuse, stint of music playing, bout of drinking etc)

wind / news / style / custom / manner / CL:陣|阵[zhen4],絲|丝[si1]

air vent / opening for ventilation

ventilation duct

air vent / louvre

filtration equipment