Possessive Nouns. Possessive nouns are used to indicate ownership. Possessive nouns usually are formed by adding an apostrophe (') and s. When a noun is plural and ends in s, just add an apostrophe ('). If two people own one thing, add the apostrophe and s to the second person only. If two people own separate things, add the apostrophe and s for each person.
Types of antibiotics. There are hundreds of different types of antibiotics, but most of them can be broadly classified into six groups. These are outlined below. Penicillins (such as penicillin and amoxicillin) â widely used to treat a variety of infections, including skin infections, chest infections and urinary tract infections.
What is an Antibiotic? Antibiotics kill bacteria, not archaea, fungi, or protists. The discovery of the antibiotic penicillin in the 1920s made a big impact on human history. Not only did it lead to a cure for bacterial infections that were once deadly, but it also led a big interest in finding new antibiotics. Today many different types of antibiotics are available, and they fight infection in several ways.