Mauna is not just about controlling the speech, but also it will lead to quiet the thoughts.
By limiting our actions and speech, it will lead us to slow down the thought waves. This will lead us into meditation.
Through talking, we are losing our prana especially if we are speaking harsh words and lies, slandering, gossiping, censuring, condemning, destructive speech and all types of negative complaints and criticisms.
If we need to talk, may it be kind words, truthful, constructive, motivating, encouraging, uplifting and cheering.
Speaking and sharing the truth of Dharma with all without any discrimination is still consider Mauna. If we need to speak Dharma to the people who are in need of Dharma speech, we should not be stubborn or attached onto observing silence and refuse to speak Dharma to desperate living beings.
Anyway, speech or languages are very restricted and conditioned. Most of the time misunderstanding occurs because of misinterpretation of the meaning of the words that is being spoken, because everybody might have different interpretations of words in different languages.
That’s why sometimes the best speech is being silent.
Dharma can never be fully explained or expressed through the limited speech and is difficult to be understood by the conditioned perception of the mind. Not many people can grasp the real meaning of Dharma through listening and reading the Dharma. The best way of understanding and knowing the Truth is through self-inquiry and self-realization. Despite that, we still can share the knowledge of Dharma with other beings through speech and writing, or else it will be less opportunity for people to come in contact with the valuable Dharma.
Any speech that is pure and intention-less does not contradict with the practice of Mauna.
If we are observing Mauna not speaking for many months and years, but we still have lots of impure and evil thoughts in our mind and performing lots of impure and evil actions, then that is not Mauna at all.
When other people are speaking lies and condemning us, or being unkind to us, and if we know how to forbear all kinds of insult or humiliation, and be patient, compassionate and forgiving, and remain silent and calm without the need of self-justification or react towards any unkind speech and actions, being undisturbed or undetermined by other people's freedom of thinking, action and speech, then this is the highest Mauna of all.
The real Mauna is inclusive of total self-control over all the impurities of thoughts, actions and speech. It's not just about not talking, but continue to express the ceaseless thoughts through the sign language, facial expression and body language.