info.pr
name.pr
// these aren't mentioned on nic.pr, but on https://www.iana.org/domains/root/db/pr.html
est.pr
prof.pr
ac.pr

// pro : http://registry.pro/get-pro
pro
aaa.pro
aca.pro
acct.pro
avocat.pro
bar.pro
cpa.pro
eng.pro
jur.pro
law.pro
med.pro
recht.pro

// ps : https://www.iana.org/domains/root/db/ps.html
// http://www.nic.ps/registration/policy.html#reg