作业精灵老师示例：
I eat some vegetables every day. I usually have some rice, some meat and
some vegetables for lunch. I sometimes eat cakes, chocolate and sweets. I
eat some fruit every day. I sometimes eat a lot at dinner. My score is twelve.
I have a healthy diet. My friend John eats some vegetables every day. He
usually has some rice and some meat for lunch. He always eats cakes,
chocolate and sweets. He eats a little fruit every day. He always eats a lot
at dinner. His score is six. He has an unhealthy diet.
