Answer:
The students attended the protest, because they are concerned about climate change.
The students attended the protest, but afterward they realized that nothing will change.
The students attended the protest, so now they're telling everyone about it.
Step-by-step explanation:
Conjunctions are words used to connect words, phrases, and clauses. They can be:
- coordinating - used to connect independent clauses. There's seven of them: and, but, for, nor, or, so, and yet.
- subordinating - used to connect subordinate (dependent) clauses to independent clauses, e.g. because, when, after, although, etc.
The first sentence became a complex sentence because a new dependent clause is introduced by the subordinating conjunction because.
The second and the third sentence changed from simple to compound sentences as a new independent clause is introduced by a coordinating conjunction (but and so).