My grandpa is (watering the flowers).对括号内提问
问题描述：
My grandpa is (watering the flowers).对括号内提问
答
where is your grandpa
答
What is your grandpa doing?对“正在浇花”提问，应用疑问词What
答
What's your grandpa doing?
方法：原句的意思是：我的爷爷正在浇花。
问题是：对“浇花”进行提问
所以应该问：你的爷爷正在干什么？（这样的题要把原句的“我”变成“你”）
答
What's your grandpa doing?
答
what is your grandpa doing?