Thefirststepinthestudyofanylanguageisobservingand____preciselywhathappenswhennativespeakersspeakit.
Asthepressure____,theliquidrockisforcedupthroughchannelsintheresistantrocktotheearth’ssurface.
Allofusknow,color-blindpeopleoftenfinditdifficultto__betweenblueandgreen.
Idon’tunderstand____believehim.
Perhapsthecustomerhas____hismonthlystatementandnotpaidthebill.
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