Follow is the way of a simple sentence into one simple sentence

1 using a particle

Andrew jumped up. He ran away

Jumping up, Andrew ran away

Smith was tired of play; he sat down to rest

Being tired of play, Smith sat down to rest

2 using a noun or a phrase 

This is my friend Watson. His name is Watson

This is my friend Watson

I spent two days in grade town; it is one of the most attractive spots in Lahore Pakistan

I spent two days in garden town, one of the most beautiful spots in Lahore Pakistan

3 using a preposition with a noun or gerund

The sun rose their journey was not started

The sun rose before the start of their journey

Joe had failed many times he still hopes to succeed

In spite of many time failures, Joe hopes to be succeed 

Her husband died. Aliya heard the news she fainted

On hearing the news of her business loss, Aliya fainted 

4 using the nominative absolute construction

The soldiers arrived, the police  the crowd disappeared

The soldiers having arrived, the mob dispersed 

5 using an infinitive  

We have some duties we must perform.

We have some duties to perform

Raj wanted to educate his son he sent him to Europe

Raj sent his son to Europe to be educated

Kumar is very fat; he cannot run

Kumar is too fat to run 

6 using an adverb or adverbial phrase

Ali deserved to succeed; he failed 

Ali failed undeservedly

The sunrise, the boys, had not started the game 

The boys had not started the game by sunrise

Combination of two or more simple sentences in a single compound sentence

Simple sentences can be combined to form a compound sentence by the use of coordinate conjunction, and there are four kinds of coordinate conjunction cumulative adversative alternative and illative

Cumulative

Conjunctions that usually add one statement to another are called cumulative.

Andrew is a fool Andrew is a knave 

Andrew is a fool and a knave 

[Or] Andrew is both a fool and a knave 

[Or] Andrew is not only a fool but also a knave

[Or] Andrew is a fool as well as a knave 

It is noticed that conjunction and simply adds one 

 statement to another

The conjunction used above, like both not only but also as well ass are emphatic forms of and do the same work.

Conjunction that usually expresses contrast or opposition between two statements is called Adversative.

Anwar is slow. he is sure

Anwar is slow, but he is sure 

Babar was Annoyed. he kept quiet

Babar was annoyed yet ( or still) he kept quiet

Smith was alright. He was fatigued

Smith was all right; only he was fatigued

You can notice that the conjunctions used above (but still yet nevertheless however express the opposition or contrast between the sentence.

Conjunctions that express a choice between two different alternatives are called alternative

Study hard; you will be fail 

Study hard, or you will be fail

Come in, Go out 

Come in or go out 

[Or] either come in or go out

You can notice that the conjunctions used in the above sentence ( either neither nor )expressed the choice among two alternatives.

Conjunction that expresses the reasoning are called illative 

Ahmed was obstinate. He was punished

Ahmed was obstinate therefore, he was punished

He can not see it is very dark

He cannot see for it is very dark

It is raining heavily you should take an umbrella with you

It is raining heavily so you should take an umbrella with you

You can notice that the conjunctions( therefore for so etc.) used In the above sentence express the reasoning from the other 

Combination of two or more simple sentences to a single complex sentence 

1 when a subordinate clause is  a noun clause 

Ahmed will be late that is certain 

It is certain that Ahmed will be late 

Anwar is short-sighted; otherwise, he is fit for the post 

Except that Anwar is short-sighted, he is appropriate for the post

The examples that are given above the subordinate clause is a noun clause 

2 When subordinate clause is an Adjective

Aliya keeps her ornament in a safe this is a safe

This is safe where Aliya keeps her ornament 

A fox met lion the fox had never seen a lion before

A fox who had never seen a lion before met him

The examples that are given above is the adjective clause

3 when a subordinate clause is an adverb 

ZA Bhutto died in 1989. Benazir Bhutto became prime minister

When ZA Bhutto died in 1989, Benazir Bhutto became prime minister

I waited for my brother. I waited till his arrival

I waited for my brother until he came 

The example is given above is the adverb clause of the subordinate.

so that is all about synthesis of sentences if you any doubt question or suggestion you may contact us in comment section