HSK 1.0 (1992)	Big5	Gb	Pin	Eng
B	空前	空前	kong4qian2	unprecedented
D	前所未有	前所未有	qian2 suo3 wei4 you3	unprecedented

HSK 2.0 (2010)	Big5	Gb	Pin	Eng
6		空前绝后	kong1 qian2 jue2 hou4	unprecedented and never to be duplicated/ the first and the last/ unmatched/ unique

HSK 3.0 (2022)	Big5	Gb	Pin	Eng
1	右	右	yòu	right side as side of precedence, right side, west, winger, right, the right side, the Right, the right
3	領先	领先	lǐng xiān	lead, lead (in competition), precede, lead_up, be in lead, show, be in the lead, get the jump
4	位於	位于	wèiyú	be situated, situated, locate, precede, lie, come, nestle, subsist, underlie, sit, be located, skirt, rank
6	稿子	稿子	gǎozi	draft of a document, script, manuscript, mental plan, precedent
7	慣例	惯例	guànlì	custom, pattern, practice, manner, tradition, routine, law, wont, habit, codex, ritual, convention, convenance, consuetude, usual practice, rule, use, observance, institution, modus operandi, precedent, conventionality, rite, praxis, natural law
7	僅次於	仅次于	jǐn cìyú	second only to..., (in second place) preceded only by...
7	空前	空前	kōngqián	unprecedented
7	口子	口子	kǒuzi	hole, opening, cut, gap, gash, my husband or wife, classifier for people (used for indicating the number of people in a family etc), precedent
7	前所未有	前所未有	qiánsuǒwèiyǒu	unprecedented
7	史無前例	史无前例	shǐwúqiánlì	unprecedented in history
7	先例	先例	xiānlì	antecedent, precedent

The rain was preceded by wind .	雨前有风。
There is no precedent for such a case .	此类案例尚无先例。

雨前有风。

此类案例尚无先例。