People concerned with the environment and global warming usually try to reduce their carbon output by increasing their home's energy efficiency and driving less. Some start by calculating their carbon footprint to set a benchmark -- like a weigh-in before a diet. A carbon footprint is simply a figure -- usually a monthly or annual total of CO2 output measured in tons. a.
Everyone should reduce their carbon output.
c.
People concerned with global warming should know their carbon footprint so they will know how they can reduce their carbon output.
b.
You should always calculate your carbon footprint before going on a diet.
d.
Everyone puts out tons of CO2 into the atmosphere every day.

based on the biblical principle proverbs 16: 32, i agree with the author of the passage "better is it that it takes longer to be angry than the strong " to the extent that i share the philosophy that the nobility of heart demonstrates the strength of a person. those who are very proud, get angry easily and show their anger toward others are really weak, but those who are noble and do not constantly obfuscate or contain their feelings of anger, are strong people

sentences vary by structure as well as by function. there are compound, complex, and compound-complex sentences.

simple sentence

i like to read.

a simple sentence has one independent clause.

compound sentence

i like to read, and i also like to write.

a compound sentence includes more than one independent clause, connected by a coordinating conjunction (and, but, for, nor, or, so, or yet).

complex sentence

i prefer to read books that are bestsellers.

a complex sentence includes one independent clause and one or more dependent clauses. (a dependent clause is one that cannot stand alone.) types of dependent clauses include relative clauses (i kicked the boy who pinched me), adverb clauses (i am going home now because i have a curfew), and noun clauses (i don't know what to do next).

compound-complex sentence

although i prefer to read current bestsellers, i do like to read old agatha christie mysteries, and i also like some 20th-century science fiction.

compound-complex sentences take a bunch of clauses (multiple independent clauses, and one or more dependent clauses) and toss them together like a salad. although these sentences take practice to write in a grammatically correct fashion, they can hold a tremendous amount of meaning, and are common in academic writing.