2306. A verb is sometimes used to denote obligatory action. This is
called the _Obligatory Use_ of the verb: as,
#paulisper commorātus est#, _Mil._ 28, _he had to wait_. #aegra
trahēbant corpora#, V. 3, 140, _they had to drag their sickly frames
along_. #caruī patriā#, _Sest._ 145, _I had to keep away from the
country of my birth_. #senātor populī Rōmānī pernoctāvit in pūblicō#,
_V._ 4, 25, _a senator of Rome was fain to sleep in the streets_.
#serēmus aliquid in dērelictō solō#, _Br._ 16, _we shall have to sow
something in an abandoned field_. #erat summa inopia pābulī, adeō ut
foliīs equōs alerent#, Caes. _C._ 3, 58, 3, _there was an utter lack of
fodder, so that they were fain to feed their horses on leaves_.