The phrase "at some presentations" is correct and usable in written English.
It can be used when referring to specific instances or occasions where presentations are given, indicating that the statement applies to a subset of those presentations.
Example: "At some presentations, the speaker emphasized the importance of audience engagement."
Alternatives: "during certain presentations" or "in some cases of presentations".
In providing an overview of the symposium and the theme of Lead Remediation Effectiveness we have drawn on information from some presentations at the symposium, besides those described in this volume.
Once I returned to my Newburyport office from New York, a couple of voice-mail messages from local Wyeth reps were already waiting for me, inviting me to give some presentations at local doctors' offices.
(From 8 to 9 P.M., PBS will broadcast some presentations at the music hall on "Broadway '98: Launching the Tony Awards"). "Beauty Queen," by the young Anglo-Irish dramatist Martin McDonagh, and "Art," by the Iranian-born French playwright Yasmina Reza, are nominated for best new play; Arthur Miller's "View From the Bridge," produced by the Roundabout Theater Company, for best revival.
Under the name of Two Boffins, we have made some presentations at private parties, with projections and some sound tests to see if people liked it live.
Of course, it's looking a little rough – this was probably a prototype on show at some internal presentation.
Phoebe Philo of Céline restricts photography, refusing to allow attendees to shoot smartphone pictures at some of her presentations and supplying news media outlets with her own photos only when the collections arrive in stores.
A little bit of shock at some of the presentations, and sadness.
Dr. del Piñal has published more than 100 original papers and book chapters and presented some 500 presentations at national and international meetings.
At the recruiting presentations, some students saw the women's colleges as their best route to the United States.
Some of networks are very active, which is visible at their internet presentations, while some others seem to be not so active.
