A complex sentence is made up of a main clause and a subordinate clause connected to each other with a subordinating conjunction. Subordinating conjunctions are common in academic writing, and they are extremely useful for indicating sophisticated connections between ideas. A subordinate clause is an incomplete sentence and cannot be used on it's own. Some examples of subordinate clauses:

• His first job as a minister in Washington, D.C. was short-lived because his abolitionist views clashed with those of his congregation. (subordinating conjunction + subordinate clause)
• The majority of staff voted in favour of the proposal while there was one against and a few abstentions.

A subordinate clause can go either before or after the main clause. For example:

• Some causes are mainly unilateral whereas others like vitamin A deficiency are often bilateral.
• Whereas few people set out deliberately to defraud in this way, there is a risk of unintentional plagiarism.

Note, if the subordinate clause comes first, a comma is used to separate it from the main clause.

Below are some of the most common subordinating conjunctions:

• after
• although
• as
• because
• before
• even though
• if
• once
• since
• so long as
• though
• unless
• until
• when
• whenever
• whereas
• wherever
• while

Adverbs

In academic writing, it is common for writers to use adverbs to connect ideas. Typically, adverbs are found at the beginning of a sentence, or they can occasionally be placed between the subject and the verb.

• However, a small group cannot file abbreviated accounts at Companies House.
• These brief summaries, however, in no way do justice to the actual performances
• Nevertheless, given the rapid advance of mobile phone technology, they look adequately antiquated to meet many purchasers ' needs.
• Typically, children have a period of normal language development, followed by a period of language regression.

Moreover, adverbs can be formed with a preposition + noun.

• By contrast, the average Congolese wage is $ 100 a year.
• In general, they will to continue to use professional firms of accountants to prepare these accounts.
• In particular, this dive site is notable for the numerous snakelocks anemones to be found clinging to the steep rock surfaces.

 Complex sentences are more common in academic writing, and more effective than compound sentences because they allow the writer to express much more sophisticated connections between ideas.