If time is seen as a fixed position on a temporal scale when an action takes place or to which a state applies, this fixed position is referred to as a time-position adverbial. Time-position adverbials may be as narrow as a point in time or as broad as a century. For instance:
Fēijī sān diǎn líng wǔ fēn dàodá .
(The airplane arrived at 3:05.)
Tā shì xīngqītiān dào de .
(He arrived on Sunday.)
Zhōngguó gǔdài kēxuéjiā Zhāng Héng yú gōngyuán èr shìjì chūshēng.
(Zhang Heng, an ancient Chinese scientist, was born in the second century A.D.)
The verb endorses the narrowness or broadness of the time referred to by the adverbial. In (1b, c) for instance, Achievement verbs 到‘dao’ (arrive) and 出生‘chūshēng’ (was born), which describe a punctual or momentary action, rule out the broad time span expressed by the time-position adverbials. Therefore, the time adverbials refer to a span of time within which, at some point in time, the events take place.
 Loar, J. K. (2011). Chinese syntactic grammar: functional and conceptual principles. New York: Peter Lang.