Do you know?
The first radios began in the 1920s,At that time the sound was very poor .So peo-ple had to listen on headphones.
Television began in the 1930s. It was black and white. In the 1960s,the TV pro-grammes began to have colour.
Do you know when computer begin?
这道题请用简单的句子写出答案，小学生基本上能读懂。大约5－6句话。
Let’s guess.Who’s that?
A man looked at a photo and said: “That person’s father is my father’s son.. I’ve no brothers or sisters. Who is he ?
參考答案:Do you know?
Computer began in the 1940s.It was very big and heavy.So people can not move it.In the 1960s,there are more and more computers.
Let's guess
It's me.是"我"
