1. Does she often come to see us? Who often comes to see us? Why does she often come to see us? Does she often or seldom come to see us? She often comes to see us, doesn't she?
2. Do my children often swim in the river? Who often swims in the river? Where do my children often swim? Do my children often swim in the river or in the lake?
My children often swim in the river, don't they?
3. Did he go on business to Moscow? Who went on business to Moscow? Where did he go on bisiness? Did he go on business to Moscow or to New York? He went on business to Moscow, didn't he?