Pair up* Pair off

 If people pair up or are paired up, they form a pair, especially in order to do something together.
  [V P with n] They asked us to pair up with the person next to us and form teams...
  [pl-n V P] Men and teenage girls pair up to dance...
  [pl-n be V-ed] Smokers and nonsmokers are paired up as roommates. [Also V n P with n]

pair off [phrasal verb]
1 : to join together in a romantic relationship
• He hated being single while his friends were pairing off and having kids.
2 pair off or pair (someone or something) off or pair off (someone or something) : to join with someone or something else to form a group of two
• People paired off for the next dance.
• She paired the students off. = She paired off the students.