It can be solo singing or playing or dancing.

可以是指独唱，独奏，独舞等。

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The opera features unique solo singing, refined acting, rich percussion and funny comedians.

戏剧的特点是拥有独特的唱腔、优美的表演、丰富的配乐、滑稽可笑的喜剧演员。

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Every member contributes to the rap, singing either solo or as part of a rap chorus.

每个成员都在为这首说唱乐出力，或者独唱，或者参与说唱合唱。

《柯林斯英汉双解大词典》

Recent conflicts and rural to urban migration that reduced the population of the region and changes in ways of life have caused a sharp decrease in the number of performers, resulting in the loss of many archaic styles and genres of solo singing.

UNESCO: CULTURE

Gaelic folk singer Julie Fowlis says she used to be "terrified" of singing solo in public.

BBC: Brave singer Julie Fowlis: 'I was terrified of singing'

She rose to stardom quickly, singing solo and mostly in Hebrew or English, packing concert halls and performing for Israeli officials and foreign delegates.

WSJ: Iran and Israel Can Agree on This: Rita Jahanforuz Totally Rocks