Final answer:
The uds./ellos/ellas form of poder in the irregular preterite tense is 'pudieron,' which is used to talk about past abilities or possibilities for a group or formal you-plural.
Step-by-step explanation:
The uds./ellos/ellas form of poder in the irregular preterite is pudieron. This form is used when talking about an ability or possibility in the past that was either fulfilled or not by a group of people or by "ustedes" (formal you-plural in Spanish).
For example, the sentence "Ellos pudieron llegar a tiempo para el concierto" translates to "They were able to arrive on time for the concert" in English, indicating that they managed to fulfill the action of arriving on time.