3. Joe usually studies Maths in the morning .对划线部分Maths提问What (subject) does Joe usually study in the morning?Joe usually studies Maths and Chinese in the morning .如果科目超过两个了问句中的subject是不是就用复数。答案就应该是：What subjects does Joe usually study in the morning? 麻烦再问一道题4. Classes start at 8 a.m. .对划线部分at 8 a.m.提问谢谢啦是的4. Classes start at 8 a.m. .对划线部分at 8 a.m.提问When do classes start?