Deciduous teeth first teeth seen in the mouth are the mandibular centrals and the last are the maxillary second molars. The primary teeth are made up of central incisors, lateral incisors, canines, first molars, and secondary molars; there is one in each quadrant, making a total of four of each tooth. All of these are gradually replaced with a permanent counterpart except for the primary first and second molars; they are replaced by premolars. The replacement of primary teeth begins around age six, when the permanent teeth start to appear in the mouth, resulting in mixed dentition. The erupting permanent teeth cause
I Should Have Known Better scene of "A Hard Day's Night". It was in fact filmed in a van, with crew members rocking the vehicle to fake the action of a train in motion. Paul McCartney is seen lip-syncing in the song in both the train scene and in the live performance at the end of the film, despite not singing in the actual recording. I Should Have Known Better "I Should Have Known Better" is a song by English rock band the Beatles composed by John Lennon (credited to Lennon–McCartney), and originally issued on "A Hard Day's Night", their soundtrack for the film of