沟通

to join / to connect / to link up / to communicate

ditch / gutter / groove / gully / ravine / CL:道[dao4]

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)

oral communication (psychology)