I was sitting the surgical waiting area at the hospital waiting for word of my wife's operation The small room was filled with other families and friends,who were1waiting to hear how their loved ones were doing.

    There was a young boy siting quietly in the2He held a small box of 3in one hand and a tablet(写字板）in the other Every so often he'd place the tablet on his lap and draw something.As the hours passed I began to see the room almost4And there was a strange silence.

    "Daddy, when is Mommy going home?"the young boy asked,breaking the 5

    "Tomorrow." his father replied The boy picked up his crayons(蜡笔）and6something on the tablet.

    I7 him as he moved his feet back and forth,looking up at the ceiling and then toward the sunshine-filled window.When's8Daddy?"he asked. His father 9 him over to sit by him."Come,10here next to me."he said with a gentle tone in his voice11his things,the little boy walked slowly to his father's side from the corner.The man12out and held his son by his shoulder.

    There are three days in life Yesterday today and tomorrow.One is over and done,one we live in,the other we 13We cant live in yesterday, but if we are happy enough today. we will be even happier tomorrow."he said in an attempt to14the boy.

    The little boy looked at him for a moment and said."If Mommy is going home tomorrow.I'll be15So.I want it to be tomorrow already. Daddy"

    Now hanging on every word of this16I leaned forward to hear his response.It was17.

    “Son, the one great thing about today is once it18it is already almost tomorrow.”

    I thought about how19 it was. Even in my adult life,I still live waiting for what tomorrow may 20.

    Now I know that it is already“almost tomorrow”.

（进价、售价均保持不变，利润=销售收入﹣进货成本）

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                                                                                              背向大地的爱
       ①父亲带着七岁的女儿去十里外的村子走亲戚。原本阴沉的天色，渐渐变得越来越黑。父亲对女儿说：“我们要快点儿走了，天可能要下大雨。”   
       ②天上铅灰的乌云越聚越浓，天色越来越暗，仿佛真正的黑夜来临。闪电如利剑一次又一次刺穿黑暗，雷声伴着狂风隆隆滚过天际，然后像炸弹一样在头顶炸裂。
       ③女儿瑟缩着小小的身子：“爸爸，我怕！”他将女儿紧搂在胸前：“丹丹不怕，把头埋进爸爸衣服里，闭上眼睛睡觉。”
       ④一道雪亮的闪电划过大地，他突然听到一种奇怪的呼啸声由远而近向自己的方向逼来。这声音像几十台拖拉机同时爬坡发出的吼声，又像无数条响尾蛇同时发出的嘶嘶声。在闪电的强光里，他看到一个顶天立地的巨大黑色烟柱飞速移来——龙卷风！
       ⑤他大骇，他知道龙卷风的厉害。小时候经历过一次，所到之处，大树齐腰斩断，树皮被剥掉，只剩白花花的树干，地上的东西被吸上天空，人和牲畜都会被摔死！ 
       ⑥他本能地想要加快脚步。但一刹那间，脚下陡然失去了支撑，身子被一股巨大的力量吸得轻飘飘。他知道此刻他和女儿都被吸到了高空，几分钟后就要被抛到九霄云外，然后粉身碎骨！ 
       ⑦“爸爸，我怕！”紧紧贴着父亲胸膛的女儿颤声叫道。“乖女儿，爸爸在和你做飞的游戏呢，你不是一直想像小鸟一样自由飞翔吗？我们现在跟许多小鸟一起飞翔呢，闭紧眼睛，我们开始数小鸟，一只，两只，三只„„” 
       ⑧他感觉自己像一个面团一样被一只巨手揉来揉去，五脏六腑都翻腾起来。他什么也不敢想，只是尽力地躬身将女儿更紧地搂住。 
       ⑨不知道过了多少时候，他感觉这只巨手的力量渐渐小了，身体也开始慢慢下降， 他知道龙卷风风力渐小，开始将吸入的物体抛向地面了。女儿，我的女儿，他心里痛苦如焚。  
       ⑩突然，他感觉自己的背撞到了什么东西，这个东西以一种强大的力量勒过他的衣服，勒进他的背--电缆！他心里滚过一阵狂喜，一瞬间，他一手搂紧女儿，另一只手拼尽力气死死抓住那根电缆！ 
       ⑪他就这样单手悬吊着支持父女两人的重量。 
       ⑫天慢慢地变亮了，狂风也小了。渐渐地，他感到手臂发软打颤，被深勒过的后背正在流血。然而不等血滴进土地，就被吹散在风中。最要命的是，女儿睡着了，睡着后的女儿会不自觉地放松抱紧父亲的双手！他不敢再往下想。 
       ⑬女儿的手一点点松开他的身体。不能再犹豫了，他看到脚底十多米的地方是一块旱地，他搂紧女儿，紧抓电缆的那只手一松，他就成了一个背朝大地面向天空的自由落体。 
       ⑭此刻怀里的女儿正在睡梦中甜甜地呓语着。他笑了。
       ⑮父亲保住了性命，却多处骨折并重度脑震荡；而女儿，毫发无伤，睡醒了还天真地对父亲说：“爸爸，我看到了好多好多可爱的小鸟，真美啊。” 
       ⑯有人问他：“你知道不知道，你这次是侥幸从死神手里逃掉的？因为你这样背对地面从高空摔下，极有可能丢掉性命。”他憨憨地说：“我知道，但如果我不这样背对地面，我的女儿就可能丢掉性命。” 
       ⑰父亲这句简单朴实的话，七岁的女儿现在还不懂。等她长大了，她会懂得，父亲对她的爱，比父亲背对的大地，还要深沉，还要厚重 。（有删改）

下列各项中的两种物质既不是同分异构体，也不是同系物的是(  )