Srimad Bhagavatam Canto 10, Chapter 33, Text 07

SB 10.33.7

pada-nyasair bhuja-vidhutibhih sa-smitair bhru-vilasair
 bhajyan madhyais cala-kuca-pataih kundalair ganda-lolaih
svidyan-mukhyah kavara-rasanagranthayah krsna-vadhvo
 gayantyas tam tadita iva ta megha-cakre virejuh
 
Translation: 
 
As the gopis sang in praise of Krsna, their feet danced, their hands gestured, and their eyebrows moved with playful smiles. With their braids and belts tied tight, their waists bending, their faces perspiring, the garments on their breasts moving this way and that, and their earrings swinging on their cheeks, Lord Krsna’s young consorts shone like streaks of lightning in a mass of clouds.
 
Purport: 
 
Srila Sridhara Svami explains that according to the analogy of lightning flashing in clouds, the perspiration on the lovely faces of the gopis resembled drops of mist, and their singing resembled thunder. The word agranthayah may also be read agranthayah, meaning “loosened.” This would indicate that although the gopis began the dance with their hair and belts tightly drawn, these gradually slackened and loosened.
 
Srila Visvanatha Cakravarti points out that the gopis were expert at exhibiting mudras (precise hand gestures that express feelings or convey meanings associated with the theme of a performance). Thus sometimes Krsna and the gopis would artistically move their interlocked arms together, and sometimes they would separate arms and exhibit mudras to act out the meaning of the songs they were singing.
 
The word pada-nyasaih indicates that the gopis artistically and gracefully placed the steps of their dancing feet in an enchanting way, and the words sa-smitair bhru-vilasair indicate that the romantic movements of their eyebrows, smiling with love, were most charming to behold.
Srimad Bhagavatam Canto 10, Chapter 33, Text 06
Srimad Bhagavatam Canto 10, Chapter 33, Text 08