I don't think you'd use a comma there in any circumstance. It's a list of two places, joining with a single and is appropriate.

Not applicable here, as "Trinidad and Tobago" is a single name in a list of two items. But a comma following "Tobago", while not a serial comma sensu stricto, would still aid comprehension.

You wouldn’t have an Oxford comma in a two item “list”. It’s for a series of three or more items.

Perhaps an exception if one of those items has an "and" in the middle?

I’ve been thinking about the same since I saw your comment. I think a comma after Tobago: “Trinidad and Tobago, and in Suriname” would make the sentence easier to understand but it also might add meaning that isn’t there. Does the added comma imply that primary object (most of the work) was done on Trinidad and Tobago, while the work in Suriname is smaller or less important?

But Trinidad and Tobago is just one place.

Exactly, that's my point!

That's why they said "and in Suriname". The "in" makes it clear.

I'm surprised some hyphen aficionado hasn't tried hyphenating that country's name because it's "too confusing".

Is it any different than Bosnia and Herzegovina? Or Sao Tome and Principe?

Exactly the point, err, comma.

Actually, the use of the preposition with each item makes this perfectly clear and unambiguous without any gratuitous added punctuation.

“in Trinidad and Tobago and Suriname” (aside from any issue with conventional use of “on” for the former) would be awkward.

Since its a two-item list, an Oxford comma would never be appropriate, so it can't signal the need for it.

No, that is why you need a semicolon. The Oxford comma is good as well, but what you showed was where a semicolon is called for.

I don't think a semicolon is right here. Are you proposing this?

"He spent a sabbatical conducting field work on Trinidad and Tobago; and in Suriname."

That sounds very odd indeed — I wouldn't say the sentence with a semicolon-sized gap in it and reading it with one is jarring.

There's nothing wrong with the original sentence. When I read and say it I do so with the same cadence as "He spent a sabbatical conducting field work on Bermuda and in Suriname." The "and" in Trinidad and Tobago is just coincidence — it's not part of the sentence structure. If a reader doesn't know that Trinidad and Tobago is a place then perhaps the sentence's "in x and y and on z" would provoke them into finding this out.

> He spent a sabbatical conducting field work on {Trinidad and Tobago} and in {Suriname}

Could be clearer, although "On Trinidad and Tobago" doesn't make sense. "In Trinidad and Tobago", or "On Trinidad", or "On Tobago", sure, but Trinidad and Tobago are two islands (and many smaller)

I was taught to use a semicolon when both fragments can stand alone as discrete sentences.

I was taught the semicolon is when you have a list within a list.

Did he meet any interesting Trinidad and Tobagoans? Or is it Trinidadian and Tobagon?

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