If they are 18 or over and their course is at degree level, they can usually stay in the UK for up to 3 years, or up to 5 years for a PHD.
Os yw'n 18 oed neu'n hŷn a bod ei gwrs ar lefel gradd, fel arfer gall aros yn y DU am hyd at 3 blynedd, neu hyd at 5 mlynedd ar gyfer Doethuriaeth.