WhenTomwasalittleboy,healreadyknewthesun ____________ thecenterofthesolarsystem.(is, was)
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IhaveworkedheresinceI ____________fromcollege.(graduated, have graduated)
Bythetimeyougetback,greatchanges _____________ inthisarea.(will takeplace, will have taken place)
ShetoldmehernameonlyafterI ____________hertwice.(had asked, asked)
Hesaidhe ____________ areportsincetwoo'clockthatmorning.(have been writing, had been writing)