Thescientistshavebeenmakingtheexperimentforhalfayear,butthey ____________yet.(haven'tsucceeded, hadn't succeeded)
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Hiswife ____________ tocatchthelasttrain,butshewastoolate.(hoped, had hoped)
Thedinnerwasthemostexpensivemealwe ____________ (have ever had, had ever had).
Inthisareamentakeofftheirhatswhenawoman ____________ the room. (enters, entered)
Afterdrivingforthirtymiles,Marysuddenlyrealizedthatshe____________inthewrongdirection.(had been driving, have been driving)