BytheendofOctoberthey ____________theyear'starget. (have hit, will have hit)
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It is known that hydrogen ____________ the lightest element.(is, was)
Wehadmeanttotellherthenews,but ____________ shewasn'tin.(find, found)
Thescientistshavebeenmakingtheexperimentforhalfayear,butthey ____________yet.(haven'tsucceeded, hadn't succeeded)
Hiswife ____________ tocatchthelasttrain,butshewastoolate.(hoped, had hoped)