Heavy Construction
The Allen and Greenough is still under construction;
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402.
 Verbs compounded with á, ab, dé, ex, (1) take the simple
Ablative when used figuratively; but (2) when used literally to
denote actual separation or motion, they usually require a
preposition (§426.  1): -  
-  (1) conátú
désistere (B.  G.  i.  8), to desist from the
attempt. 
 - désine commúnibus
locís  (Acad.  ii.  80), quit commonplaces. 
 - abíre
magistrátú, to leave one's office. 
 - abstinére
iniúriá, to refrain Irom wrong. 
 - (2) á própósitó
aberráre (Fin.  v.83), to wander from the point. 
 - dé próvinciá
décédére  (Varr.  ii.  48), to withdraw
from one's province. 
 - ab iúre abíre  (id.  ii.  114), to go outside of the law. 
 - ex cívitáte excessére
 (B.  C.  vi.  8), they departed from the state.  [But ef finibus suis axcassarant (id.  iv.  18), they
had left their own territory.] 
 - á mágnó
démissum nómen Iúló (Aen.  i.  288),
a name descended (sent down) from great Iulus. 
 
 
For the Dative used instead of the Ablative of Separation, see
§ 381.  For the Ablative of the actual place whence in idiomatic
expressions, see §§427.1, 428.f.  
a. Adjectives denoting freedom and want
are followed by ablative: -  
-  urbs núda praesidió
 (Att.  vii.  13), the city naked of defence. 
 - immúnis mílitiá
 (Liv.  i.  43), free of military service. 
 - plébs orba tribúnis 
(Leg.  iii.  9), the people deprived of tribunes. 
 
 
NOTE:  A preposition sometimes occurs: -  
-  á culpá vacuus
(Sail.  Cat.  14), free from blame. 
 - líberí á
déliciís (Leg.  Agr.  i.  27), free from
luxuries. 
 - Massána ab his rebus vacua atque
núda est (Verr.  iv.  3), Messana is empty and bare of
these things. 
 
 
For the Genitive with adjectives of want, see §349.  a.