根据情境及首字母提示填入适当的单词，使短文句意完整、通顺。
Pen pal wanted
   His name is Wang Lei. He is a____ C_____ boy. He wants a pen pal in____ F_______ . He thinks it’s a very____ i______  country and he wants to learn some French. He____ l_____  in Beijing, China with his parents now. He is 14 ____  y______  old and his____ b______  is in November. He can speak Chinese and a little English. What are his ____  l______ ? He likes watching sports games on TV and ____  p_____ computer games with his friends. His favorite subject is computer science. It’s____  f______ . He doesn’t like math, because it’s too difficult.
   Please write to____ h____ and be his pen pal.

一遥控小汽车正在跑道上做加速直线运动，现在通过遥控柄将其加速度逐渐减小，则它的（　　）

家庭是社会的基本细胞，是人生的第一所学校。不论时代发生多大变化，我们都要重视家庭建设，传承优良家风。家风（    ）

①是中华文化的重要表现形式     ②是封建社会的家庭伦理

③蕴含着丰富的中华传统美德     ④能解决现阶段的主要矛盾

____+45=____+55，这里运用了加法____，用字母表示是____．