①是什么声音，像一串小铃铛，轻轻地走过村边？____

②三月的桃花水，难道没有催促村民们开犁播种吗？____

③三月的桃花水，日夜不停地、快乐地向前流淌。____

④小草和麦苗在春天里谈心。____

根据文章内容和括号内所给汉语的意思，写出各单词的正确形式（每空一词）。

Dear Dad,

    Father's Day is coming. Although I am ____（忙）getting ready for the high school entrance exams, I want to celebrate it for you because you are my ____（英雄）. I'd say, “I love you, Dad!”

    I do think you are the most ____（耐心）father in the world. Every time I have trouble, you always give me advice and help me out. I remember ____（一次）I failed in a competition, I felt terrible. Instead of complaining, you just said to me quietly, “A real man must learn to____（面对）many failures in life bravely. Cheer up!” I repeated your words many times and finally knew what ____（它的）meaning was.

    Dad, I am going to buy you a ____（明信片）as a present. I hope you will like it although I don't think it can ____（表达）all of my thanks to you. I believe you can ____（理解）me. Love you forever, Dad!

Best ____（祝愿）!

Yours,

Mike

如图所示，在容器底部固定一轻质弹簧，弹簧上方连有长方体木块A，容器侧面的底部有一个由阀门B控制的出水口，当容器中水深为20cm时，木块A有一半的体积浸在水中，此时弹簧恰好处于自然状态，没有发生形变．（不计弹簧受到的浮力，g取10N/kg．）

（1）求此时容器底部受到的水的压强；

（2）求木块A的密度；

（3）向容器内缓慢加水，直至木块A刚好完全浸没水中，立即停止加水，此时弹簧对木块A的作用力为F₁，在原图上画出此时水面的大致位置；

（4）打开阀门B缓慢放水，直至木块A刚好完全离开水面时，立即关闭阀门B，此时弹簧对木块A的作用力为F₂，求F₁、F₂之比．