Why does the writer tell the story of his making a lemonade drink at the end of the passage?

TOPIC: What three qualities do you most expect in a friend? The text you should base your composition on is On Friendship. Use the following outline as a guide:　　? Introduction (you name the three qualities)　　? Body (you develop what you have mentioned in the introduction)　　? Conclusion (you summarize what you have written)

苏珊的父母一向以她为荣，并为她取得的进步和成绩而高兴.

这幅油画中的老房子使我想起了我在乡下度过的童年.

从高中时起，他就梦想成为一名医生现在，他正努力实现自己的梦想.

在危急时刻.他总是能够保持清醒和冷静

There’s a ___ moment towards the end of the film, when they eventually see each other again, (delight)

现在许多消费者购物时更愿意用支付宝(Alipay)或微信(WeChat)付款.

It doesn't take much to improve the energy ___ of your home. (efficient)

Mistakes are always ___ , if one has the courage to admit them, (forgive)

The professor's knowledge and experience contributed ___ to the success of our project, (immense)