Is this a dictionary?改成否定句

Is this a dictionary?改成否定句 This is a pagoda.改成否定句 This is a dog改成否定句 This is a map of China(改成否定句） Is this a ruler?怎么改成否定句 this is my ruler改成否定句 this is my eraser.改成否定句 This is his backpack.改成否定句 this is his ring改成否定句 that is notebook（改成一般疑问句） s is Lucy is dictionary?（改为否定句） This is our new timetable.改成否定句.英文句 she is a teacher 改成否定句