摘要：For past-time reference, Present-Day English (PDE) has a choice between the
present perfect (I have seen her) and the simple past tense (I saw her). With temporal
adverbials like yesterday or last week, the simple past (SP) is usually
required. Adverbials like since, just and yet tend to be used with a present perfect
(PP). The distinction between SP and PP is a fairly recent development in
English. Since the distinction was not clear-cut in British English (BrE) when
the first settlers arrived in America, its scarcity in American English (AmE) has
been interpreted as an aspect of colonial lag. Data from late Modern English
indicate that this is not really the case. The long-range, corpus-based study by
Elsness (1997) shows that the PP increases over time but starts decreasing again
from the second half of the eighteenth century. This development is led by AmE,
but the decrease starts from a higher level than in BrE.
