The structure 放着…不…
The structure 放着…不… 
means "to give up something and not do it". We can use this structure to express that there were conditions or opportunities to do something valuable, but a person decided not to do it.
means "to give up something and not do it". We can use this structure to express that there were conditions or opportunities to do something valuable, but a person decided not to do it. Pay attention
This structure is used in spoken language.
Scheme
subject
放着
object
valuable opportunity
不
predicate
…
Examples
他放着律师的工作不做，回来当农民
He left his job as a lawyer and came back to be a farmer
tā fàngzhe lǜshī de gōngzuò bú zuò, huílái dāng nóngmín
我们干吗放着快艇不坐，非要坐帆船呢？
Why should we take a sailboat instead of a speedboat?
wǒmen gànma fàngzhe kuàitǐng bú zuò, fēi yào zuò fānchuán ne
最大难题是很多学生放着生活感受不写，他们写不熟悉的一些东西
The problem is that many students don't write about their life experiences. They write about things they are not familiar with
zuì dà nàn tí shì hěn duō xuéshēng fàngzhe shēnghuó gǎnshòu bù xiě, tāmen xiě bù shúxī de yìxiē dōngxi