Question

you should take some medicine（改为否定句） Tom had bett

you should take some medicine（改为否定句）
Tom had better stay at homet（改为否定句）
I have to look after my mother at home.（ 同义句转换。）
你应该遵循医生的建议。（完成译句）

Answer 1

you shouldn't take any medicine.
Tom hadn't better stay at home.
i must look after my mother …
翻译如下：you should follow your doctor's adivce.

追答

更正一下，第二个是，had better not

Answer 2

第一个在should后面加not
第二个had better后加not
第三个have to前面加don not
You need to follow the doctor's advice.

Answer 3

you shouldn't take some medicine

追答

Tome hadn't better stay homet