纪念币

Pinyin: jìniànbì
Meaning：Commemorative coin
Sentence：作者对世界各国发行的足球世界杯纪念币进行了系统的研 究。The author systematically studied World Cup soccer commemorative coins issued by various countries in the world.

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纪：

Pinyin: jǐ, jì
Meaning: Period; order; record; discipline; age; era
Radical: 纟
Stokes: 6
Traditional: 紀
Common words/Phrase:
纪要[jìyào] 【summary of a meeting log】
纪律[jìlǜ] 【discipline】
纪实[jìshí] 【on-the-spot record】
纪元[jìyuán] 【beginning of an era】
纪录片[jìlùpiàn] 【newsreel】

念：

Pinyin: niàn
Meaning: To read aloud
Radical: 心
Stokes: 8
Traditional: 念
Common words/Phrase:
念头[niàntou] 【idea】
念书[niànshū] 【read】
念经[niànjīng] 【patter】
念珠[niànzhū] 【prayer beads】
念叨[niàndao] 【talk over】

币：

Pinyin: bì
Meaning: Money; coins; currency
Radical: 巾
Stokes: 4
Traditional: 幣
Common words/Phrase:
币制[bìzhì] 【currency system】
币值[bìzhí] 【value of a currency】
币金[bìjīn] 【coin gold】
货币[huòbì] 【money】
钱币[qiánbì] 【coin】