- Keen - surudoi , 鋭い
- Laborer - rōdōsha, 労働者
- Machine - kikai, 機械
- Nail polish - manikyua, マニキュア
- Oasis - oashisu, オアシス
The first word is a mixture of kanji and hiragana. I was happy when I look through the dictionary on laborer and machine and found out it's written in kanji and it also sounds like mandarin. As for nail polish and oasis, it's in katakana.