I had come across this interesting lesson on Du Chinese, called "Did you do it for nothing?"
Essentially, it's about a Chinese idiom for doing something in vain.
If you go to your friend's house to hang out, but he/she isn't at home, then your trip was in vain. You might then say,
"我白来了！" "wǒ bái láile!" ("I came in vain!", literally, "I white/blank came")
白 bái, which literally means "white" or "blank", is used idiomatically to describe a wasteful activity.
Someone I follow on Twitter tweeted a photo of a student protesting during the shortlived "color revolution" over the weekend of November 26th-27th. As per the fad or fashion of the protesters, they were holding up a blank sheet of paper.
It immediately struck me that the protests (that had by then fizzled out) could be aptly described by the Chinese idiom that I'd learnt.
So I tweeted:
我"白"抗议了！ wǒ "bái" kàngyìle! ("I protested in vain!", or literally "I white/blank protested!")
A number of people "liked" my tweet. Most gratifying of all was the comment by @HarrietInForest:
先生您的中文太棒了吧！xiānshēng nín de zhōngwén tài bàngle ba! ("Sir, your Chinese is amazing!")
I felt a burst of encouragement, a feeling of
加油! jiāyóu! ("Come on!" or "More power to you!", literally "Add fuel!")
I was doubly gratified. (1) I was being praised (however undeservedly) for my language skills, and (2) I had successfully made a witty remark in a language I was still learning.