COFFEE

drinking coffee makes me concentrate

and it's a good drink to wake me up...haha!

BUT

If i didn't eat anything before i drink coffee,i will get stomachache...

It's not a good feel.

and

if you get used to drink in high caffeine,it will make you dirnk more more coffee a day.

so i quit this custom.

I drink tea now.

紅茶，green tea is my fevorite drink.