untimely [ un- = not 不；timely a. & ad. 及時的，及時地→]I a. at a wrong time or season 不適時的，不合時宜的 / Snow in June is untimely. 六月下雪是不合時令的。II ad. too early or young 過早地/ Her death came untimely at 18. 她在18 歲的時候就過早去世了。

unreasonably [ un- = not 不；reasonably ad. 合情合理地→]ad. in a way that is not reasonable; foolishly; extremely 不講道理地；不理智地；過分地/ A miser is unreasonably stingy. 守財奴都小氣得不近人情。

unemployment [ un- = lack of 無；employment n. 就業(yè)→]n. lack of employment; being out of work 失業(yè)；失業(yè)狀態(tài) / Unemployment has become the top problem in the country. 失業(yè)巳成為該國的頭號問題。 

unrest [ un-= lack of 無；rest n. 安靜，安寧 →]n. lack of ease or quiet; disturbance or agitation 不安，不寧；動亂，騷動 / The lasting unrest in the area eventually led to a rebellion. 該地區(qū)持續(xù)的動蕩不安終于導(dǎo)致一場暴動。

unbend [ un- = to undo 取消；bend v. 彎→“to undo that of bending取消彎曲的狀態(tài)”→]v.① straighten弄直；伸直/ Can you unbend this crooked nail?你能將這根彎釘子弄直嗎？②relax 放松，使松懈 / She unbent her mind after work by watching television. 做完工作，她看電視散散心。

untie [ un- = to undo 取消，tie v. 綁→“to undo that of tieing 取消捆綁的狀態(tài)”→]v. undo a knot, etc. ; loose解開；放松/ Please untie the package.請解開包裹。