How to say you didn't need to buy the book. in Japanese
1)
君君(kun) (pn) you/buddy/pal/monarch/ruler/sovereign/masterは(int) indicating a subject/yes/indeed/well/ha!/what?/huh?/sighそ(n,adj-na) sparse/not closeのの(no) (prt) indicates possessive/nominalizes verbs and adjectives/substitutes for "ga" in subordinate phrases/indicates a confident conclusion/ indicates emotional emphasis/indicates question本本(hon) (n) book/volume/script/this/present/main/head/real/regular/counter for long cylindrical things/counter for films, tv shows, etc./counter for goals, home runs, etc.をを(wo) (prt) indicates direct object of action/indicates subject of causative expression/indicates an area traversed/indicates time over which action takes place/indicates point of departure or separation of action/indicates object of desire, like, hate,買う買う(kau) (v5u,vt) to buy/to purchase/to value/to have a high opinion/to stir/to provoke必要必要(hitsuyou) (adj-na) necessary/needed/essential/indispensable/necessity/need/requirementが(prt) indicates sentence subject/indicates possessive/but/however/still/andなかった(v) didn't haveのにのに(noni) (prt) although/when/and yet/despite this/in spite of/even though/but even so/but even then/however/nevertheless/for all that/notwithstanding that/while/if only/i wish/i tell you/you should do/in order to。。(。) Japanese period "."
