pin sth↔down

ˌpin sth↔ˈdownto explain or understand sth exactly确切说明（或理解）The cause of the disease is difficult to pin down precisely.病因目前还难以解释清楚。

• Agrapha
• as sound as a bell
• refoldings
• pigmented paper
• go unanswered / unnoticed / unrewarded etc
• as dry as a bone
• by the sea
• dandriffy
• in no time (at all) / in next to no time
• prosecuting attorneys
• electrolyte acids
• mascles
• wakenings
• talbutal
• exequies
• nemean gamess
• density stratification
• quaternized
• opinionaire
• closed-loop recycling
• demasculinize
• electrical response
• craniom.
• hung shot
• social / personal / sex etc life
• exhaust-suction stroke
• propound
• go-kart
• benzyl fluoride
• localise
• thermometric
• Cunningham, Glenn
• snot-rag
• olid
• borschts
• hgwy
• AFIPS
• an only child
• disenroll
• responsory
• triple threater
• backing up
• ericeticolous
• theridiids
• clocks
• hard-lining
• for all -
• metabolism
• arsenides
• auding
• gray market
• criminalised
• black as a as coal
• move (或loosen) one's bowels
• ullage
• canada balsams
• Gattermann reaction
• key click
• Rydberg atoms
• caponizing
• amateurships
• thermal farad
• favourablest
• osteofibroma
• stemhead
• well-reputed
• Advanced Technology Bomber
• wind cave national parks
• cointegrates
• trot ... out
• reassimilate
• ADPase
• sac fungus
• interplay
• silicone rubber
• muscle out
• condottieres
• prosect
• holographic memory
• squaccos
• critically ill / injured
• hardhead
• breeze into
• Water Carrier
• snogs
• carolyns
• anaphor
• Hopkins,Harry Lloyd
• master terminal
• polariton
• superelevation
• monotonists
• half subtracter
• homestall
• mine detection
• forced-draft
• tree-goose
• doctorly
• endoscopic
• calcium hypophosphite