Communicate, in a way, can be done in a variety of ways. Speaking is the most common form of communication, and it can be done with five letters: SPEAK. Rapping is another form of communication, which is done with three letters: RAP. PHONE calls are also a popular form of communication, and it can be done with five letters: PHONE. Lastly, telex is an older form of communication that is still used today, and it can be done with five letters: TELEX.