Tā quàn péngyǒu zhuājǐn jīhuì: huākāikānzhézhíxūzhé, mòdàiwúhuākōngzhézhī.
She urged her friend to seize the chance: 'when the flower blooms, pluck it directly - don't wait till it's gone to snap a bare branch.'
Tips
history
Closing line of 杜秋娘《金缕衣》 (Du Qiuniang, attrib., Tang, c. 9th c.): 劝君莫惜金缕衣，劝君惜取少年时。花开堪折直须折，莫待无花空折枝 (I urge you not to treasure the gold-threaded robe; I urge you to treasure your youthful years. When the flower blooms and may be plucked, just pluck it - don't wait till it's gone to break the empty branch). Du Qiuniang was a Tang courtesan-turned-consort; the poem is both carpe-diem advice and a warning about wasted opportunity.
usage
空 here = classical 'in vain / to no purpose,' not 'empty' in the physical sense. 莫 = classical negative imperative ('don't'). Canonically preceded by 花开堪折直须折; the couplet is almost always cited as a pair.
