unexpectedly
To be unprepared means to be unprepared. It comes from the sixth chapter of Yang Yuru's Xinhai Revolution: the Qing army was caught off guard and retreated.
Idiom explanation
It means that things come suddenly and make people unprepared.
The origin of Idioms
Source: the sixth chapter of Yang Yuru's Xinhai Revolution is "the two bridges of Qing army's retreat.".
Analysis of Idioms
Caught off guard
unexpectedly
Holding ice in winter and holding fire in summer - dōng hán bào bīng,xià rè wò huǒ
the order , once given , will be strictly enforced - yán chū fǎ suí
make a feint to the east but attack in the west - shēng dōng jī xī
It's better to be skilful than to accumulate money - jī cái qiān wàn,bù rú bó jì zài shēn
by cutting out the superfluous - shān fán jiù jiǎn