Number + 根 + Noun
The measure word 根 (gēn) is used to count long, thin objects such as sticks, rods, hairs, strings, and pipes. It is placed between a number and the noun it modifies. For example, 一根筷子 means 'one chopstick' and 一根管 means 'one pipe.'
桌子上放着两根筷子。
Zhuōzi shàng fàng zhe liǎng gēn kuàizi.
There are two chopsticks on the table.
她从头上拔下一根白头发。
Tā cóng tóu shàng bá xià yī gēn bái tóufa.
She plucked a white hair from her head.
我需要买几根绳子来绑箱子。
Wǒ xūyào mǎi jǐ gēn shéngzi lái bǎng xiāngzi.
I need to buy a few ropes to tie up the boxes.