In order to become a fossil, specific conditions need to be met. An organism needs to die in the right place. It must avoid scavengers and decomposers that would destroy its remains, and it needs to have hard body structures. Soft body structures will decay. Even if a fossil does form, it might not be found. Fossils are sometimes crushed, weathered, eroded and even melted before they are ever discovered. Based on the passage, which of these best describes fossils?

A. rare to find and hard to form
B. often formed but never found
C. always crushed and often soft
D. common to find and easy to form

a complex sentence consists of an independent clause and one or more dependent clauses.  

to write complex sentences, we must use subordinating conjunctions.  

all the complex sentences begin with a subordinating conjunction and when it occurs, a comma must be place at the end of the dependent clause. on the contrary, if the sentence begins with an independent clause, then no comma is used.

after  

although  

as  

because  

before  

if  

since  

when  

for example,  

after she won the competition, she became very popular.  

although my father was hurt, he continued fighting for his rights.  

as all of you got a ten, you will be able to leave early today.  

before he went to the war, he asked his parents to bless him.  

if it is cold, i won’t go out.  

since you didn’t bring the homework, you will get low grades.  

when it is hot in the town, everyone goes to the beach.