Vocabulary consisting only from characters you are able to read
特急
とっきゅう
limited express train (faster than an express train)jlpt4, ryokou
説く
とく
to explain, to advocate, to preach, to persuadegodan, verb
研ぐ
とぐ
(1)to sharpen, to hone, to whet, to grind, (2)to wash (rice), (3)to scour, to polish, to burnish godan, verb, vtrans