Order of Words in a Sentence

To make meaningful sentences we need to arrange words in a particular order. The usual order of words in an English sentence is as follows:

Subject

In an affirmative sentence, the subject usually comes before the verb.

She is my friend. (Subject - she, verb - is)
It is my bag. (Subject - it, verb - is)
The dog barked. (Subject - dog, verb - barked)

Interrogative sentences usually begin with an auxiliary verb followed by the subject.

Is she your friend? (Auxiliary verb - is, subject - she)
Is it your bag? (Auxiliary verb - is, subject - it)
Did the dog bark? (Auxiliary verb - did, subject - dog)

Object

The object usually comes after the verb.

He killed the snake. (Subject - he, verb - killed, object - snake)
I love my mother. (Subject - I, verb - love, object - mother)

When there are two objects, the indirect object (which usually denotes a person) usually comes before the direct object (thing).

She brought me a cup of coffee. (Indirect object - me, direct object - cup of coffee)
I told them a story. (Indirect - them, direct - story)

Adjective

When an adjective is used attributively, it comes before the noun it qualifies.

Few children came.
She is a beautiful girl.
He is a lazy boy.

When an adjective is used predicatively, it comes after the verb.

She is beautiful.
He is lazy.

Adverb

An adverb is usually placed close to the word it modifies.

He is a rather lazy boy. (Here the adverb rather modifies the adjective lazy.)
I was pleasantly surprised. (Here the adverb pleasantly modifies the verb surprised.)

Phrases and clauses

Phrases and clauses should be placed close to the words they modify.

She left the bread that was too hard to eat on the counter. (Here the clause 'that was too hard to eat' modifies the noun bread.)
I bought a clock with crooked hands from the shop. (Here the phrase 'with crooked hands' modifies the noun clock.)

Notes

For the sake of emphasis we sometimes alter the normal order of words in a sentence. For instance, words that need to be emphasized are usually placed at the beginning of the sentence.

Compare:

Though he was intelligent, he couldn't solve the problem.
Intelligent though he was, he couldn't solve the problem. (Here the emphasis is on the word intelligent.)

Another common practice is to begin sentences with adverbs or adverb phrases.

The annual examination will start tomorrow.
Tomorrow the annual examination will start.
The strong wind howled outside.
Outside, the strong wind howled.
I visited Paris during the summer.
During the summer, I visited Paris.

Note that adverbs sometimes need a comma after them.