Bythetimehewastwelve的精選

問題詳情： Bythetimehewastwelveyearsold,he ____achemistrylabofhisown.   A.hadbeensetup        B. hadsetup C.havebeensetup        D. havesetup【回答】B知識點：動詞時態與語態題型：選擇...