vOcAbUlArY woRds

Shrewd-astute and penetrating, often with regard to business

2. artful and crafty a shrewd politician

3. Obsolete

a.  piercing a shrewd wind

b.  spiteful

shrewd in my own words............... smart,sharp,intelleqent.

impromptu-without being planned
synonyms-unprepared,extempore,improvised,spontaneous
. Prompted by the occasion rather than being planned in advance: an impromptu party.

2. Spoken, performed, done, or composed with little or no preparation; extemporaneous: a few impromptu remarks.