50 Complex Sentence Examples (Grammar, Structure & Uses)

In order to construct English language structures, complex sentences serve as basic structural elements. Understanding complex sentences does not require concern from you.

Learning their functionality makes complex sentences straightforward to operate.

Here, you will learn about completing a sentence with complexity while gaining expert guidance on their application.

What Is a Complex Sentence

A sentence becomes complex through the combination of a single main independent clause together with multiple subordinate dependent clauses.

A sentence starting with a dependent clause needs a comma before continuing with another clause.

These structures can also unite through subordinating conjunctions that include “although,” “unless,” and “because.”

Examples of complex sentences include:

• We proceeded to the park despite unfavorable weather conditions. 
• Had I studied harder, I would have succeeded in the exam. 
• We took a detour because heavy traffic conditions delayed us. 
• While she spent time preparing for exams, her brother spent time watching television.
• Until you try new foods, you’ll never know your favorite dish.

The Role of Subordinate Clauses in Complex Sentences

A subordinate clause is a clause that cannot stand on its own as a complete sentence.

It complements a sentence’s main or independent clause, thus adding a whole unit of meaning.

Because a subordinate clause is dependent on the main clause, it is also called the dependent clause.

A subordinate clause functions as a dependent clause that delivers supporting information to a main sentence regardless of its name.

Dependent clauses in writing start with subordinating conjunctions to establish a connection with the main clause. 

Several subordinating elements exist in the English language for clause connections, such as while, when, whenever, where, wherever, before, for, as, since, hence, provided that, therefore, consequently, though, due to, because, unless, once, and after.

They can also begin with relative pronouns such as which, who, whom, that, whichever, whoever, whomever, and whose.

50 Complex Sentence Examples (With Explanations)

Complex sentences allow us to express relationships between ideas with precision.

The examples below illustrate how complex sentences work in practice and explain their structure and function.

Temporal Relationships (When/Before/After/While)

1. When the storm finally passed, we ventured outside to assess the damage. (The subordinate clause “When the storm finally passed” establishes when the main action occurred.)

2. Before officially accepting the position, James examined the company’s reputation. (The subordinate clause indicates something that happened before the main clause.)

3. The children played in the garden while their parents prepared dinner in the kitchen. (The subordinate clause shows simultaneous actions.)

4. After she graduated from university, Maya traveled through Southeast Asia for six months. (The subordinate clause establishes a sequence of events.)

5. Whenever I visit my grandmother, she insists on cooking my favorite childhood meals. (The subordinate clause indicates a recurring temporal relationship.)

Causal Relationships (Because/Since/As)

6. Because the traffic was unusually heavy, we arrived thirty minutes late to the conference. (The subordinate clause explains the reason for the main clause.)

7. Since you’ve already completed the preliminary research, we can move directly to the analysis phase. (The subordinate clause provides the reason for the conclusion in the main clause.)

8. The team celebrated enthusiastically as they had exceeded their sales targets for the third consecutive quarter. (The subordinate clause explains the cause of the celebration.)

9. The historic building was renovated because its structural integrity had been compromised. (The subordinate clause gives the reason for the renovation.)

10. As the technology continues to evolve, companies must adapt their strategies accordingly. (The subordinate clause establishes a causal relationship with ongoing implications.)

Conditional Relationships (If/Unless/Provided That)

11. If the weather improves tomorrow, we’ll go hiking in the mountains. (The subordinate clause establishes a condition for the main clause to occur.)

12. You won’t be considered for the position unless you submit your application before the deadline. (The subordinate clause presents a necessary condition in negative terms.)

13. The project will proceed as planned, provided we secure the necessary funding. (The subordinate clause establishes a specific condition that must be met.)

14. If you had told me about the problem earlier, I could have helped you find a solution. (The subordinate clause presents an unfulfilled condition in the past.)

15. You can borrow my car whenever you need it, as long as you fill-up the tank afterwards. (The subordinate clause establishes a conditional relationship with a stipulation.)

Concessive Relationships (Although/Though/Even Though)

16. Although it was raining heavily, the outdoor concert proceeded as scheduled. (The subordinate clause presents a contrast or unexpected circumstance.)

17. Though the research findings differed from expectations, the experimental outcome was still successful. (The subordinate clause indicates an exception that does not counteract the original statement.)

18.  Alex achieved the summit before the experts due to his novice status, although he had never scaled a mountain before. (The subordinate clause creates a contrast that makes the main clause more remarkable.)

19. The small business continued to thrive, although the economic conditions were challenging. (The subordinate clause presents circumstances that generally prevent the main clause’s outcome.)

20. Although I acknowledge your viewpoint, I maintain a different conclusion about it. (The subordinate clause acknowledges a point before contrasting with it.)

Purpose Relationships (So that/In order that)

21. The professor spoke slowly so that the international students could follow the lecture more easily. (The subordinate clause explains the purpose of the action in the main clause.)

22. We left early so that we would have time to stop at the historical site on our way. (The subordinate clause indicates the intention behind the action of the main clause.)

23. The company invested in new technology to increase productivity in the long term. (The subordinate clause states the purpose of the investment.)

24. The instructions were translated into multiple languages so that they would be accessible to all employees. (The subordinate clause explains why the action in the main clause was taken.)

25. The scout moved quietly through the forest so that he wouldn’t alert any wildlife to his presence. (The subordinate clause indicates a negative purpose—preventing something.)

Relative Clauses (Who/Which/That)

26. The woman who won the marathon trained at high altitudes for six months. (The subordinate clause identifies which woman is being discussed.)

27. The book everyone has been discussing finally arrived at our local library. (The subordinate clause specifies which book is meant.)

28. Solar panels, which convert sunlight into electricity, are becoming increasingly affordable. (The subordinate clause provides additional, non-essential information about solar panels.)

29. Students who complete all the assignments will receive extra credit. (The subordinate clause defines which students will receive extra credit.)

30. The historic building, which was constructed in the late 19th century, is being restored by a team of specialists. (The subordinate clause adds non-essential information about the building.)

Result Relationships (So…that, Such…that)

31. The concert was so popular that tickets sold out within minutes of becoming available. (The subordinate clause indicates the result of the situation described in the main clause.)

32. It was such a complex problem that even the experts were puzzled by it. (The subordinate clause shows the consequence of the extreme degree mentioned in the main clause.)

33. The storm caused such extensive damage that the town took months to recover. (The subordinate clause illustrates the result of the extreme condition.)

34. The child was so excited about the surprise that she couldn’t sleep the night before. (The subordinate clause shows the result of the emotion.)

35. The evidence was so compelling that the jury reached a verdict after brief deliberation. (The subordinate clause indicates the consequence of the persuasive nature of the evidence.)

Manner Relationships (As if/As though)

36. She spoke about her experiences as if she had been there herself. (The subordinate clause describes the manner of speaking by drawing a comparison.)

37. The new employee approached the challenge as though she had been handling such situations for years. (The subordinate clause indicates the manner through comparison.)

38. The athlete moved as if gravity didn’t apply to him. (The subordinate clause uses an impossible comparison to describe manners.)

39. He stared at the painting as though he could see beyond the canvas. (The subordinate clause describes the manner of looking through comparison.)

40. The child treated the stray dog as if it were a long-lost friend. (The subordinate clause describes manner through an emotional comparison.)

Place Relationships (Where/Wherever)

41. I’ll meet you where the path divides near the old oak tree. (The subordinate clause specifies the location for the meeting.)

42. Wherever the team plays, their loyal fans follow to support them. (The subordinate clause indicates a generalized location relationship.)

43. The archaeologists concentrated their excavation where the ancient texts had indicated a temple once stood. (The subordinate clause provides the location information for the main clause.)

44. The guide led us to where the river narrows between two cliffs. (The subordinate clause specifies a location defined by a geographical feature.)

45. The child hid where his parents would never think to look. (The subordinate clause indicates the strategic choice of location.)

Comparison Relationships (Than/As)

46. The solution was more complicated than we had initially anticipated. (The subordinate clause establishes a comparison between expectation and reality.)

47. The experiment results were not as conclusive as the researchers had hoped. (The subordinate clause sets up a comparison between desired and actual outcomes.)

48. The new policy has been more effective than anyone predicted at the outset. (The subordinate clause creates a comparison between prediction and outcome.)

49. The city looks very different than it did when I lived here twenty years ago. (The subordinate clause establishes a temporal comparison.)

50. The recovery process took longer than the doctors had estimated. (The subordinate clause compares expected and actual timeframes.)

Complex vs. Simple vs. Compound Sentences

Each sentence type requires a different understanding because they function to achieve distinct communication needs while affecting writing impact. 

Simple sentences include one primary sentence part, which contains both a verb and subject while expressing a single conceptual element.

Despite their name, simple sentences might not necessarily be simple — they might be long sentences with the addition of modifiers and compound elements. Consider this example:

The ambitious young executive with an impressive track record of innovation presented her revolutionary business model to the skeptical board of directors.

This sentence, while simple in structure (one clause), communicates substantial information.

Compound sentences link independent clauses through coordinating conjunctions like and, but or, not, for, and yet while semicolons connect independent clauses or conjunctive adverbs including, however, therefore, or nonetheless serve to unite clauses.

Compound sentences differ from complex ones because they merge two equal-graded ideas with similar grammatical values. For example:

The research team collected the data, and the statisticians analyzed the results.

The relationship between these phrases shows their importance is equivalent. 

Complex sentences incorporate a self-standing independent clause joined by one or more dependent subclauses.

Writers use this structure to show main points and supporting details and to indicate how the supporting information relates to the main points.

Difference Between a Compound and Complex Sentence

Here are some examples between a compound and complex sentence:

• Structure: A compound sentence consists of two independent clauses which function as separate entities, yet complex sentences unite an independent clause with dependent clauses to support it.

• Connecting Words: The connections between compound sentences occur through conjunctions like FANBOYS (for, and, nor, but, or, yet, so), semicolons, and conjunctive adverbs. In contrast, complex sentences need subordinating words (because, although, when, if) or relative pronouns (who, which, that).

• Hierarchy of Ideas: Compound sentences maintain an equal status between separate ideas. Complex sentences provide a clear order to show the main points while indicating what plays a supporting role.

How To Identify a Complex Sentence

Here are surefire ways to identify a complex sentence:

• Look for Both Clause Types: Complex sentences require independent clauses that work independently and at least one dependent clause that cannot function separately.
• Identify Subordinating Words: Detect subordinating terms by examining conjunctions (because, alongside, although, when, and, if, together, with, who, which) and relative pronouns.
• Check Clause Position: The placement of dependent clauses comes before an independent clause and follows or interrupts it depending on correct punctuation rules.
• Observe Punctuation Patterns: A sentence beginning with a dependent clause usually needs a comma to follow both phrases. The need for a comma depends on the vital nature of the information that comes either before or after a dependent clause.

Common Subordinating Conjunctions Used in Complex Sentences

Some common subordinating conjunctions used include when, while, before, after, until, because, since, as, if, unless, provided that, although, though, even though, and so on.

How to Write a Strong Complex Sentence

Below are some of the ways to write a strong, complex sentence:

• Put your main idea in the independent clause
• Use secondary information in dependent clauses
• Choose the most precise subordinating conjunction
• Consider clause placement for emphasis
• Avoid overloading with too many dependent clauses
• Revise for clarity and impact

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Conclusion

Once you get the hang of complex sentences, you’ll see they aren’t complex.

You can construct them and improve them using the tips in this article.

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