勾通

to collude with / to conspire

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)

surname Gou

to attract / to arouse / to tick / to strike out / to delineate / to collude / variant of 鉤|钩[gou1], hook

see 勾當|勾当[gou4 dang4]