单项选择

Leadingstressmanagementexpertssaythatlif

Scientistshavealreadyfoundproblemsthatas

Thesunrisesintheeastandsetsinthewest,soi

TheEnglishlanguagehasalwayschanged,butth

Themicroscopeenablesscientiststodistingu

Languagelearningusually______consciousim

Itwasnotuntilshearrivedattheclassroomshe

Thelessthesurfaceofthegroundyieldstothew

His________behaviormadeeveryonenervous.H

Lifeinsurance,beforeavailableonlytoyoung

Somephilosophersinsistthatonewayto______

Thegovernmenthashardlytakenmeasurestocra

Thefirstrecordeduseofnaturalgastolightst

Therodent______themouse,rat,guineapig,an