單項選擇。Both his parents look sad.Maybe they
問題詳情：單項選擇。Both his parents look sad.Maybe they _________what's happenedtohim.Ａ. knew Ｂ. haveknown Ｃ. mustknow Ｄknow【回答】Ｂ知識點：動詞時態題型：選擇題...
問題詳情：單項選擇。Both his parents look sad.Maybe they _________what's happenedtohim.Ａ. knew Ｂ. haveknown Ｃ. mustknow Ｄknow【回答】Ｂ知識點：動詞時態題型：選擇題...