“临时准备”怎么说？是一个单词来的

impromptu / extemporaneous / makeshift

im·promp·tu (ĭm-prŏmp'tū, -tyū)
adj.
Prompted by the occasion rather than being planned in advance: an impromptu party.
Spoken, performed, done, or composed with little or no preparation; extemporaneous: a few impromptu remarks. See synonyms at extemporaneous.
adv.
With little or no preparation; extemporaneously.

n.
Something, such as a speech, that is made or done extemporaneously.
Music. A short composition, especially for the piano, performed in an offhand or extemporized style.
[French, from Latin in prōmptū, at hand : in, in; see in–2 + prōmptū, ablative of prōmptus, readiness, from past participle of prōmere, to bring forth. See prompt.]

im·promp·tu (ĭm-prŏmp'tū, -tyū)
adj.
Prompted by the occasion rather than being planned in advance: an impromptu party.
Spoken, performed, done, or composed with little or no preparation;