Compound sentences

Compound sentences => Sentence which consist of two simple sentences each contains { Subject + Predicate + Compliment/ Object}

Compound sentences with semicolons [;]
A third way to form a compound sentences is to connect the two independent clauses with a semicolon alone :
Example : Poland was the first Eastern European country to turn away from communism; others soon followed  

at that example the blue one is Independent Clause and the purple too. and related each other

this kind of compound sentence is possible only when the two independent clauses are closely related in meaning. If they are not closely related, they should be written as two simple sentences, each ending with a period. 
 Example : 

1. The practice of yoga strengthens the body and promotes flexibility; it also strengthens the mind and refreshes the soul {addition combine, Similar idea}
2. Motherhood causes some women to quit her jobs; other continue working despite having young children {opposite combine}
3. Three hundred guests attended his wedding; two attended his funeral {part combine}

Conjunctive adverbs 

1. To add a similar, equal idea

>> Also, Besides, Furthermore, in addition, moreover, as well, too 

Example :

• Community colleges offer preparation for many occupations; also/besides/furthermore/in addition/moreover, they prepare students to transfer to a four-year university. 
• Community colleges offer preparation for many occupations; they prepare students to transfer to a four-year college university as well. 
• Community colleges offer preparation for many occupations; they prepare students to transfer to a four-year college or university, too

2. Too add an unexpected or surprising continuation 

 .>> However, nevertheless, nonetheless, still

• The cost of attending a community college is low; however/nevertheless/nonetheless/still, many students need financial aid. 
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