【简答题】He lay back on the grass using his backpack as a .
【简答题】He lay on the grass, and (stare) at the sky for a long time.
【判断题】发元音时,声带一定震动;发辅音时,声带一定不能震动。
【简答题】He (lay, laid) on the grass, looking at the sky.
【判断题】元音发音时,声带不一定震动;辅音发音时,声带一定震动。
【简答题】He lay on the grass, ____________(look) into the sky.
【单选题】He on the grass, looking at the sky.
【单选题】He lay ___ the grass was the thickest.