The most convincing explanation is that when someone is finding it difficult to understand what is said to them, he/she engages in a form of lip-reading: he/she will observe the lips of the talker and mimic the talker's lip movements.
Lake Tanganyika is an African Great Lake. It is estimated to be the second largest freshwater lake in the world by volume, and the second deepest, in both cases, after only Lake Baikal in Siberia; it is also the world's longest freshwater lake.
Lake Baikal is the oldest and deepest lake on Earth. It is located in southern Siberia, in Russia. The deepest and oldest freshwater lake in the world, Lake Baikal is located in southern Siberia. The lake contains about one fifth of the worldâs supply of fresh water and is also the ninth largest in surface area.