下面是某教师的课堂教学片段: T: Are you happy? Ss : Yes, we are. T: When there’s something wrong with your body, are you still happy? Ss : No. T: Look at the picture, is he happy? Ss: No, he isn’t. T: Why? Ss: (With the teacher’s help) He has a
stomachache. (Learn other phrases about illness in the same way) T: Now let’s learn a chant. Say first two lines of the chant
after me. Say the next two lines together with me according to my action. Say the last two lines by yourselves according to my action. Now let’s start: Head, head, I have a headache. I have a headache. Stomach, stomach, I have a stomachache. I have a stomachache. Ear, ear, I have an earache. I have an earache. Tooth, tooth, I have a toothache. I have a toothache. Back,
back, I have a sore back. I have a sore back. Throat, throat, I have a sore throat. I have a sore throat.
请根据材料回答下列3个问题。