Answer:
1.
Spot ran to the door. (Highlight yellow)
2.
This is too expensive, and that is too small.
3.
Because my coffee was too cold, I heated it in the microwave.
4.
Though Mitchell prefers watching romantic films, he rented the latest spy thriller, and he enjoyed it very much.
A coordinating conjunction is a conjunction placed between words, phrases, clauses, or sentences of equal rank, e.g. and, but, or.
A subordinating conjunction a conjunction that introduces a subordinate clause, e.g., although, because.
An independent clause is a group of words that can stand alone as a sentence.
A dependent clause is a clause, typically introduced by a conjunction, that forms part of and is dependent on a main clause (e.g., “when it rang” in “she answered the phone when it rang”).