The phrase "a string of topics" is correct and usable in written English.
It can be used to refer to a series or list of subjects that are related or discussed together.
Example: "During the conference, the speaker covered a string of topics, including climate change, renewable energy, and sustainable practices."
Alternatives: "a series of topics" or "a list of subjects".
Among the counter-myths was the one about his holding forth on a string of topics at the dinner table.
Mr. Trump swung back and forth between the prepared text and a string of topics, ranging from health care, to policing in Chicago, to Mr. Trump's campaign kickoff speech, to the need for rich people running the Treasury Department, to the desire to see law enforcement officers be a little more aggressive in arrests.
During that hour-long conversation with a standing-room only crowd of MBA students, he covered a string of serious topics, including how today's newest business leaders must gird themselves for an increasingly turbulent business world, and how pushing for change rarely makes you popular with investors or employees.
"I am not going to be quoted on any of that at this point in time," Coughlin said after a string of questions on the topic.
All of which has started to push the issue towards the front of the news agenda in the Netherlands, where the country's financial daily paper, Financieele Dagblad, has published a string of articles on the topic.
A string of studies on the topic have either come to contradictory conclusions or differed substantially over the amount of energy gained by using ethanol in place of other fuels.
But for the most part, he chose to air his grievances on a variety of topics and regurgitate a string of false claims.
I became interested in this topic after a string of bad dates.
The coaching screens and reports display amazing persistence, with students patiently working through dozens of problems until they master a topic and complete a string of correct exercises.
Tyndale House Publishers, a Christian company that was founded in 1962 to print a more reader-friendly version of the Bible, has had one of its biggest successes in the last year with a string of books on a slightly less religious topic: football.
His behavior and a string of controversial and dark statements about Islam, among other topics, have alarmed many of his former colleagues.
