A sentence is a group of words arranged in a specific order which makes complete sense.

There are different kinds of sentences and they are

Reflexive pronouns are formed by the addition of the suffix self (singular) or selves (plural) to simple pronouns such as my, your, her, him, it, them and our.

A pronoun is a word used instead of a noun. Hence it must be of the same number, gender and person as the noun.

The pronouns which are used to ask questions are called interrogative pronouns. Examples are: who, what, whom, whose and which.
Interrogative pronouns may be used to ask:
a) Direct questions
Who is there?
What is your name?
Whose is this house?
What do you want?
What is there in your bag?
To whom were you speaking?

Determiners are words like the, my, this, his and Determiners are words like the, my, this, his and any. Determiners modify nouns and precede them.

Kinds of determiners

Some nouns are plural in form but singular in meaning. These nouns are always followed by singular verbs. Examples are: news, politics, physics, economics, mathematics and mechanics.

An English noun can be in either singular or plural number. The singular number denotes one person or thing. Examples are: dog, cow, cat, horse, tree, book etc. A plural noun denotes more than one person or thing. Examples are: dogs, cows, cats, horses, trees and books.