Whencarbonisaddedtoironintheproperproportions,theresultissteel.

• A.container
• B.sequence
• C.laboratories
• D.amounts

Urbanrenewalprogramsstrivetoupgradeareasthatarebecomingslums.

• A.reproach
• B.improve
• C.fortify
• D.uproot

Incalculatingthedailycalorierequirementsforanindividual,variationsinbodysize,physicalactivity,andageshouldbetakenintoaccount.

• A.numbered
• B.stabilized
• C.contrasted
• D.considered

Thecontrolsofmostmodernairplanescanbeoperatedeithermanuallyorautomatically.

• A.bythebook
• B.byamap
• C.bylogic
• D.byhand

Alligatorsstillexistinsomeofthedank潮湿swampsandbayous小海湾ofAlabama'scoastalregions.

• A.weirdly古怪的fascinating
• B.mythical
• C.drab(monotonous)
• D.unpleasantlyhumid

InthenortheasternUnitedStates,itrainsintermittently间歇地throughoutthespring.

• A.steadily
• B.abundantly
• C.periodically
• D.daily