What is the system here & where do you put XYZ ?!

Question: A EF HI KLMN T VW ?
BCD G J OPQRS U ?

Answers: A EF HI KLMN T VW ?
BCD G J OPQRS U ?

A EF HI KLMN TVWXYZ
BCD G J OPQRS U

Z
XY

?????
but i think
Z
XY

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