A vacation means the number of days or weeks that people are permitted to be off their job or their school. A vacation is necessary for their mental and physical health to lead a pleasurable life. When people are tired, they cannot
Penicillin was discovered by a Scottish scientist Alexander Fleming in 1928.1 However, a man named Laureate Howard Walter Florey was the first to use it as a medicine. Fleming found that certain blue-green molds inhibited the growth of the bacteria