Precipitation hardening
[機] 析出硬化
?? 詞語組成解析
precipitation
[pr?'s?p?'te??n]
n. 匆促;沉淀;（雨等）降落;某地區降雨等的量;
pre 前綴,表示….前的,預先#詞根助記：pre+cipit頭→ation→落在前頭→降落,下降
n. 硬化, 淬火\\n[計] 硬化, 固化, 淬火
??? 情景例句
What a country!
多奇妙的國家啊！
One good turn deserves another.
以德報德。
Come on! shouted everyone, very loudly.
“快！快呀！”每一個人都大聲地喊。