CMB should be used in times when you cannot answer the call, have to go, or when you want somebody to call back later. It is very effective in personal and professional life but particularly in meetings, traveling or when you are multitasking. Rather than typing lengthy messages, when you want someone to call you, write CMB to convey your message. It is suitable in cases when an interaction needs voice communication as opposed to long-term text messaging, and the communication process becomes smoother and more effective by both parties.
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