B
say是及物动词,后面一定得加上一个名词,如say something What didhe say just now?
tell是及物动词,后面也一定得加上一个名词 如tell sth.to sb.或者tell sb.sth.
speak作“演讲”,是不及物动词,如speak at the meeting 作“说某种语言”及物动词 如speak English
talk不及物动词talk about sth.with sb.