he is living a fast life - ano otoko wa hade na kurashi o shite iru -Not exactly. "He lives showy life. He is spending a lot of money for luxury items and funs." he is good for nothing - ano hito wa kiyo na otoko da -"That person manages everything deftly." he broke his word- ano hito wa yakusoku o yabutta -Correct beat it - nigero -"Run away!" leave it alone - hotte oke -Correct dont tell stories - uso o yuna -Correct. "iuna" is often pronounced as "yuuna" in casual conversation. cool off- ki o ochitsuke tamae -Correct.

What you need is translation from Japanese to English, right? i'll try my luck - undameshi o yatte miyo -I assume the Japanese sentence should be "....yatte miyou". (Last vowel is long.) It may be "Let's try our luck" or "I'll try my luck." i was merely joking- tada jyodan o ittano da -Correct. i tried hard but to no avail- hone o otta ga dame datta -Correct. it's up to you - kimi no kangae shidai -Correct. it is pretty tough - sore wa ochigai -Means "It's completely wrong." it is beyond my power- boku no chikara dewa dekinai -Correct. he will come to his senses- kangae naosu daro -Correct. The subject may be he or she. he is a hopeless case- ano otoko wa dame da -Correct. he is smarter than he looks - mita tokoro yori riko da -Correct. The subject may be he or she or you. he shows off - ano hito wa ibaru -Means "That person behaves arrogantly." "That person behaves as if he/she was superior than others." he has a warm heart - nasako bukai hito da -Correct. It should be "nasake bukai hito da". Otherwise it doesn't make sense. he took the matter to the heart - kare wa sono ken o shindaishita -"Shindaishita" doesn't make sense. Isn't it "shinpaishita" ? If so, it means "he worried about the matter." that is his forte - sore wa ano hito no ohako desu -Correct.

undameshi o yatte miyo ↓ うんだめしをやってみよ（運試しをやってみよ） tada jyodan o ittano da ↓ ただじょうだんをいったのだ（ただ冗談を言ったのだ） ×i tried had but to no avail ↓ ○I had tried but to no avail. hone o otta ga dame datta ↓ ほねをおったがだめだった（骨を折ったがだめだった） kimi no kangae shidai ↓ きみのかんがえしだい（君の考え次第） sore wa ochigai ↓ ？ boku no chikara dewa dekinai ↓ ぼくのちからではできない（僕の力ではできない） kangae naosu daro ↓ かんがえなおすだろう（考え直すだろう） ano otoko wa dame da ↓ あのおとこはだめだ（あの男はだめだ） mita tokoro yori riko da ↓ みたところよりりこうだ（見たところより利口だ） ano hito wa ibaru ↓ あのひとはいばる（あの人は威張る） nasako bukai hito da ↓ なさけぶかいひとだ（情け深い人だ） he took the matter to the heart - kare wa sono ken o shindaishita ↓ ？ sore wa ano hito no ohako desu ↓ それはあのひとのおはこです（それはあの人の十八番です） 十八番＝得意 ano otoko wa hade na kurashi o shite iru ↓ あのおとこははでなくらしをしている（あの男は派手な暮らしをしている） ano hito wa kiyo na otoko da ↓ あのひとはきようなおとこだ（あの人は器用な男だ） he broke his word- ano hito wa yakusoku o yabutta ↓ あのひとはやくそくをやぶった（あの人は約束を破った） nigero ↓ にげろ（逃げろ） hotte oke ↓ ほうっておけ uso o yuna ↓ うそをいうな（嘘を言うな） 言うな ↓ ×yuna ○iuna ki o ochitsuke tamae ↓ きをおちつけたまえ（気を落ち着けたまえ）