Ответ:
1. Mary is singing. She doesn't sing often
2. I somettimes like playing..., I am playing
3. Do you paint often? No, I don't. But I don't paint often
4. Tom and Mary don't usually drink coffee. Do they often drink tea? Right now they are drinking green tea
5. Are Tom and Sally having breakfast now? No, they are not. They always have luch at 11 o'clock