Difference Between Alligator vs Crocodile & Than vs Then

Anyone who’s ever paused mid-sentence wondering whether to write “than” or “then” knows that some comparisons are harder than others — the same goes for telling an alligator from a crocodile. This guide breaks down the most common “difference between” confusions, from reptile snouts to tricky homophones, with clear rules you can actually remember.

Daily searches for ‘difference between’ queries: Over 500,000 globally · Most common language confusion pair: Their vs. There · Animal pair with highest search interest: Alligator vs. Crocodile · Grammar pair most searched: Than vs. Then

The table below highlights the primary differences between these two reptiles.

This quick reference table summarizes the key distinguishing facts.

What is the difference between alligator and crocodile?

At first glance, alligators and crocodiles look like cousins that borrowed each other’s wardrobe. But a few reliable markers — snout shape, teeth visibility, and habitat — separate them cleanly. Both belong to the order Crocodylia, but they split into different families millions of years ago (HowStuffWorks (science education site)).

Snout shape and size

The single best field mark: alligators sport a broad, U-shaped snout, while crocodiles carry a narrower, V-shaped one. This isn’t a subtle difference — from above, an alligator’s head looks like a shovel, a crocodile’s like a wedge (Britannica (reference encyclopedia)).

Size also leans one way: crocodiles generally grow larger than alligators, though both groups can reach formidable lengths (IFLScience (science news outlet)).

Teeth visibility

When the jaws shut, the difference is in the smile. Crocodiles typically show the fourth tooth on the lower jaw — it sticks out like a canine — while alligators, with their overbite, hide most lower teeth (Science Focus (popular science magazine)). It’s a quick check that works even from a distance.

Habitat and behavior

Alligators are freshwater specialists, thriving in swamps, lakes, and rivers. Crocodiles, by contrast, tolerate saltwater and are common in coastal estuaries and mangrove swamps (SeaWorld (aquarium education department)). This is a rule of thumb, not an absolute — some crocodiles venture far inland, but the pattern holds across most encounters.

Crocodiles are also more aggressive on average, a trait tied to their territorial saltwater habitats (Britannica (reference encyclopedia)). Color reinforces the split: alligators are darker, often gray or black, while crocodiles tend toward olive or tan (Britannica (reference encyclopedia)).

What is the difference between than and then?

Few word pairs trip up native English speakers as often as “than” and “then.” They sound similar, but their jobs in a sentence are completely separate.

Definition of than

“Than” is a conjunction or preposition used to introduce the second part of a comparison. Examples: “bigger than a breadbox,” “more than enough.” The function: comparison only (Britannica (reference encyclopedia)).

Definition of then

“Then” is an adverb that refers to time or sequence. It answers “when?” or “what’s next?”: “First we eat, then we leave,” “Back then, things were different.” No comparison involved (Britannica (reference encyclopedia)).

Memory trick to keep them separate

• Both “than” and “comparison” contain the letter A.
• Both “then” and “time” contain the letter E.
• If you can replace it with “compared to,” use “than.” If you can replace it with “next” or “at that time,” use “then.”

The catch: this pair gets muddled most often in speed-writing — emails, text messages, first drafts. Proofread specifically for it, and the error rate drops to near zero.

What is the difference between their and there?

Another homophone hazard. “Their” and “there” sound identical but live in different grammatical neighborhoods.

When to use their

“Their” is a possessive adjective, meaning “belonging to them.” Example: “Their car broke down.” It always modifies a noun. If ownership is involved, “their” is the pick (Britannica (reference encyclopedia)).

When to use there

“There” references a place or indicates existence. Examples: “Put it over there,” “There is a problem.” Think location or the “there is/are” construction (Britannica (reference encyclopedia)).

Common mistakes

• Incorrect: “There going to the store.” → Correct: “They’re going to the store.” (They are)
• Incorrect: “I found there keys.” → Correct: “I found their keys.”
• Incorrect: “Their is no answer.” → Correct: “There is no answer.”

What this means: add “they’re” to your mental checklist. The full trio — their, there, they’re — is the real challenge, not any single pair.

What is the difference between complete and finish?

These two verbs are often swapped in everyday conversation, but careful writers draw a line between completeness and finality.

Nuance of completion

“Complete” emphasizes that every required part is present. A completed project has all components; a completed form has no blank fields. The focus is on wholeness, not end time.

Nuance of finishing

“Finish” stresses the endpoint — the action is done, regardless of whether every detail is perfect. You can finish a race without completing a marathon in the sense of covering every mile (e.g., if it’s shortened). The nuance is temporal, not holistic.

Examples in context

• “She completed the puzzle” = all pieces are in place.
• “She finished the puzzle” = she stopped working on it (likely because it’s done, but the emphasis is on the stop point).
• “The builder completed the house” = all rooms, fixtures, permits done.
• “The builder finished the house” = work ceased; context determines if it’s truly done.

The pattern: in formal writing, “complete” carries an extra layer of thoroughness. If you want to say something is fully assembled and verified, use “complete.” If you just want to say the action stopped, use “finish.”

What is the difference between two things generally?

When confronting any comparison — animals, grammar, products, ideas — a simple method turns confusion into clarity.

Step 1: Identify the items

Name each thing explicitly. “Alligator vs. crocodile” is clear. “Alligator” without specifying species is not. Precision at step one prevents cross-talk later.

Step 2: List key attributes

Write down 3-5 attributes for each item. For animals: snout shape, teeth, habitat, color, behavior. For words: part of speech, meaning, usage example. Attributes form the columns of your mental table.

Step 3: Compare side by side

A comparison table works best. Place attributes in rows, items in columns. The differences jump out visually — a pattern that a paragraph of text might obscure. Visual aids like tables are shown to improve comprehension of contrasting information.

The implication: once you have a table, the remaining work is just deciding which differences matter for your context. A zookeeper needs habitat and diet. A writer needs part of speech and example sentences. Context determines relevance.

“The difference between the almost right word and the right word is really a large matter — it’s the difference between the lightning bug and the lightning.”

— Mark Twain, often cited in language guides

“Alligators and crocodiles differ in snout shape, tooth visibility, and habitat — but of those three, snout shape is the most reliable field identification.”

— Britannica (reference encyclopedia)

For any reader navigating the English language or the animal kingdom, the core habit is the same: isolate the distinguishing feature, check it against a reliable source, and practice until the distinction becomes automatic.

For a deeper dive into the physical traits that set these reptiles apart, check out this guide on key differences between alligators and crocodiles.

Frequently asked questions