根据汉语意思完成下列句子。 1.离开房间时,关灯是很容易做到的. ___ quite easy___ _______ ______ the lights when you leave a room. 2.学生们空闲时间通常玩电脑游戏. The students usually____ computer s ___ ____ ____ ____. 3.每只海牛平均大约有10英尺长,重约1000磅. The average manatee is about____ ___ ____ and it _______about 1,000____. 4.他已经参观过他祖先居住的地方了吗? _________ he____ the 'place where his ancestors lived________? 5.当你刷牙时,不要让水龙头一直流水,要节约用水. Don't leave the tap ____while you brush your teeth. We must__________ ___________.