冰凍三尺，非一日之寒

three feet of ice does not form in a single day (idiom); Rome wasn't built in a day

ice / CL:塊|块[kuai4] / to chill sth / (of an object or substance) to feel cold / (of a person) cold / unfriendly / (slang) methamphetamine

variant of 冰[bing1]

to freeze

to freeze / to feel very cold / aspic or jelly

three / 3

one of the characters used to represent a musical note in gongche notation, 工尺譜|工尺谱[gong1 che3 pu3]

a Chinese foot / one-third of a meter / a ruler / a tape-measure / one of the three acupoints for measuring pulse in Chinese medicine / CL:支[zhi1],把[ba3]

abbr. for 非洲[Fei1 zhou1], Africa

to not be; not / wrong; incorrect / non-; un-; in-; de- / to reproach; to blame / (coll.) to insist on; simply must

one / single / a (article) / as soon as / entire; whole; all; throughout / "one" radical in Chinese characters (Kangxi radical 1) / also pr. [yao1] for greater clarity when spelling out numbers digit by digit

abbr. for 日本[Ri4 ben3], Japan

sun / day / date, day of the month

(possessive particle, literary equivalent of 的[de5]) / him / her / it

cold / poor / to tremble