out out damned spot

the worst cough to have is the type that leaves a tiny residual speck of phlegm in the deepest depths of your throat. So tiny you have to use all your might to expel it - enough to hurl your both lungs out. So minute you want to strangle yourself when you see that almost-microscopic bright green spot slide ever so fast into the drainage hole in the wash basin. All that coughing for a few seconds of existence???

白费心机。。。

it gets worse at night.