Mum: Would you like learn some traffic rules?

son: yes, I’d like.

Mum:ok, look at the traffic light. what color is it now?

son: It’s red.

Mum:Yes,.when the light is red, we should⁽³⁾ stop.

son:. Ok, mum.

Mum: what color is it now?

son:. It’s yellow.

Mum: Yes, when the light is yellow, we should wait.

son:. Yes, mum.

Mum: what color is it now?

son: It’s green.

Mum: Yes, when the light is green, we can go.

son: ok, mum, I got it.