Brain Teasers:What has everybody seen before but will never

Brain Teasers:What has everybody seen before but will never Brain Teasers:What has a mouth but never speaks? Brain Teasers:What room has no walls,no doors, no windows,an Brain Teasers:What number has nothing left if you take a hal Brain Teasers:What does everyone have and overlook? Brain Teasers 7 Brain Teasers 6 Brain Teasers 1 Brain Teasers 8 Brain Teasers 3 Brain teasers的意思是? what has a mouth but never smiles?