At the time of adolescence the changes are physically and mentally. In physically the changes are different from boys and girls and may be internal and external. Internal changes in boys:Reproductive parts will be fully developed. The voice of boys will become hoarse. External changes in boys:Facial hairs like moustache, beard begins to grow. The hairs under armpits and on chest begin to grow. Growth in height. Internal changes in girls:Reproductive parts will be fully developed. External changes in girls:The hairs under armpits begin to grow. Due to these physically changes boys and girls are mentally disturbed and suffered.. Mental behavior:They feel parents are wrong and go with friends. Their feelings are different, Sometimes they feel shy to taik with opposite sex and sometimes they wish to talk to them.Adolescence is the age of stress and confusion.