Thisisanimportantproblem_______toofewsocialscientistshaveresearched.
A、whichD
into which 引导的是 problem 的定语从句。 which 指代 problem ，into 与 research 搭配。
Lyingundertheskull,thehumanbraincontainsanaverageoftenbillionnervecellscalled______.
Idon’tmind_______thedecisionaslongasitisnottoolate.
EmpiricalstudiesshowthattheprocessofSLAisaprocessofconstructingandmodifyingrulesofcommunication.
Iwaswritingareportlastnight;________Iwouldnothavestayeduplate.
Bloomfielddrewon______psychologywhentryingtodefinethemeaningoflinguisticforms.
