Material Noun

A material noun refers to the raw elements with which objects are made. Examples are: iron, gold, silver, honey, milk, water, rice etc.
The objects made of material nouns are usually common nouns.

A noun is the name of a person, a place or a thing.

We need four chairs.
This necklace is made of gold.
Harry is a clever boy.
Tokyo is a populous city.
Paris is the capital of France.

Adverb

An adverb is a word used to modify a verb, an adjective or another adverb. Examples are: slowly, fast, kindly, afternoon, today, now and then.

There are tens of thousands of words in English, but not all words do the same job. While some words join other words together, some others express action. Some words are the names of people and things and some words tell us how something happens. Sentences are built using these different kinds of words. These words are the different parts of speech.

Adjectives are usually used before the nouns they qualify.

An honest boy
A clever fox
A beautiful girl
An old woman
A wise man

An article is basically a determiner which has little meaning of its own. English has two articles: the definite article ‘the’ and the indefinite article ‘a/an’.

Elder and older, Eldest and oldest

Elder is used to talk about people. Older can be used to talk about both people and things. Elder is usually used in speaking of members of the same family. Older is not used with this meaning.