- AN ………………ANA    CONSTRUCTION

Verb stem + AN            Repeating Verb stem + ANA

This is another repetitive  mood that gives the action the  meaning of  rush, chaotic haste, plentiness, many. 

Bu yıl matematikten kalan kalana.  ----> This year, so many people failed in Maths.

In the sentence above, 

Stating the big amount of people that is so many of them. 

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Acil´e  koşan koşana. ---> There are so many people rushing to emergency. [hospital]

In the sentence above,

1. Stating the plentiness of people, people are flooding into the emergency. [so many]

2. Stating the kind of chaos, rush, haste of people in emergency service. 

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