【计】 four frequency dilex communication
four
【医】 quadri-; Quat; quattuor; tetra-
frequency; frequently
both; double; even; twin; two; twofold
【化】 dyad
【医】 amb-; ambi-; ambo-; bi-; bis-; di-; diplo-; par
communitcate by letter; correspond; correspondence
【计】 communication