Collective nouns denote a group of people, objects, ideas, or animals as a single concept. Though the collective noun refers to more than one in a group, the noun itself is considered a single thing.However, they can be used as either singular of plural.It all depends on the sentence.Tying to decide which form to use can get confusing because you have to use the correct verb and pronoun forms, too.xamples of Collective Nouns. The singular verb and pronoun form is used is if they are acting in unison. For example: The class listens [singular verb form] carefully to its [singular pronoun] teacherâs instructions. (Here the class is a unit acting together as one.
Radiocarbon dating can only be used to determine the age of objects that were once alive, such as fossilized bones or plants. It is of no use in dating geological formations that do not contain some remains of formerly living substances.
Index fossils. Radiometric dating. The Age of Dinosaurs was so many millions of years ago that it is very difficult to date exactly. Scientists use two kinds of dating techniques to work out the age of rocks and fossils. The first method is called relative dating.