NARRATOR：

Now listen to part of a lecture in a psychology class.

MALE PROFESSOR：

I have a three-year-old daughter, and last month I decided to help her learn how to wash her hands by herself.

Now, we usually think of washing our hands as one action,

but when you think about it, you can break hand washing down into a series of simpler steps:

step 1, you turn on the water; step 2, you get your hands wet;

step 3, you add some soap; step 4, you rinse your hands, and step 5: you turn off the water.

So I broke it down into these steps, and then I helped my daughter learn them, one step at a time;

I didn’t present them all at once because that would have been too complicated.

First I showed her step 1, turning on the water.

That’s all we practiced for the next few days.

Then, when she started turning on the water by herself, I added step 2, getting her hands wet.

And for the next few days she practiced steps 1and 2,

turning on the water and getting her hands wet, until she could do both steps on her own.

Then we added step 3, putting on the soap, and she practiced steps 1, 2, and 3 for a while.

Then we added step 4, rinsing her hands, and eventually, step 5, turning off the water.

She practiced all five steps in sequence for a few days until she could wash her hands all by herself.