becomes so worn and unreliable that it eventually is not worth mending.
磨损太厉害，老得一点儿也不准了，最终会不值得修理了。
新概念英语第四册 Lesson 37 The process of ageing

📚 句中词汇解析

从本句中提取的重要词汇

eventually [ɪ'vɛntʃuəli] 词频4 词根: 行走
adv. 终于，最后;竟;总归;终究;
💡 eventual最后的+ly 表示方式、程度、状态、“...地” → ad.终于；最后
"Eventually, his anger dissipated."
他的愤怒终于平息了。
近义：sometime, lastly, ultimately, finally
worn [wɔrn] 词频2
adj. 穿旧的，用旧的;穿坏的，用坏的;筋疲力尽的; v. wear的过分词;
"the replacement of worn car parts"
汽车上损坏零件的更换
近义：outworn, pined, shabby, threadbare, torn, undermined 反义：modern, new, novel, recent, unused
worth [wɝθ] 词频1
adj. 值得的;有…的价值;等值的;有…的财产; n. 财富，财产;价值;
"Each answer is worth 20 points."
每题为20分。
近义：merit, price, pricing, rate, value, worthiness 反义：insignificance, slightness, insignificancy
mending
n. 修补工作
近义：mend, repair, repairing, darn, darning, reparation
unreliable [[ˌʌnri'laiəbl]]
a. 不可靠的\\n[法] 不可靠的, 靠不住的
近义：inconstant, nondependable, skittish, undependable, untrustworthy, wanton 反义：occasioning, reliable, sedate, serious, staid, sure

📚 更多「新概念英语第四册」例句

and by measuring the time interval between the taps and the receipt of the echoes, the depth of the sea at that point can be calculated.
测出回声间隔的时间，便可算出该处海洋的深度。
Beyond two or three days, the world's best weather forecasts are speculative,
世界上最好的两三天以上的天气预报具有很强的猜测性，
they are not prepared even to admit the possibility that noise affects people.
甚至不愿承认噪音可能对人有影响。
Many strange new means of transport have been developed in our century,
本世纪已研制出许多新奇的交通工具，
The adolescent, with his passion for sincerity,
青少年酷爱真诚，
good-tempered elephant who will give many years of loyal service.
脾气温顺、能忠实为人服务多年的大象。