Conjunction Puzzle: Is this clause dependent or independent?

Question

Third grade teacher here. I plan to teach students to distinguish between simple, compound and complex sentences — but only if I can demonstrate a clear and meaningful difference between the latter two! **Complex or Compound?** Each sentence in the following pairs is similar to its partner. 1. All dogs are mammals, *so huskies are mammals*. 2. All dogs are mammals, *therefore huskies are mammals*. 3. I come bearing soup, *for Kate is sick*. 4. I come bearing soup, *because Kate is sick*. Are the sentences above complex or compound? First, we need to decide whether each italicized clause is independent or dependent. To me, they all look dependent. If that is the case, there's not much need to teach about compound sentences. Is there a meaningful difference between the sentences in each pair that I am missing? (Are the FANBOYS as special as they'd like to think?)

Answer 1

I agree these are tricky, but my expertise tells me that in order to have a complex sentence you need an independent clause (one that can stand on its own as a complete thought) and a dependent clause (one that cannot stand on its own and is NOT a complete thought). The two clauses must be joined by a subordinate conjunction for it to quality as a complex sentence. Now that we have that out of the way...in sentence #1 the conjunction "so" is merely a coordinating conjunction and joins two independent clauses = compound sentence. In sentence #2 the word "therefore" is technically an adverb, although in this sentence it is acting as the subordinating conjunction establishing the condition between the two sentence parts = complex. Sentence #3 although the word "for" can imply the conjunction because, it does not do so convincingly, and is therefore identified as the "F" in FANBOYS and a coordinating conjunction = compound. Lastly, sentence #4 is clearly a complex sentence as the word because connects an independent and a dependent clause - the classic definition of a complex sentence.

I hope this was clear and concise enough to be of value to you...good luck!