CREATE TABLE table_15990 ("Case/Suffix" TEXT, "we two" TEXT, "you and I" TEXT, "you two" TEXT, "them two  ( the two ) " TEXT, "who-two" TEXT)

What is them two (the two) when we two is ngalbelpa?
SELECT "them two (the two)" FROM table_15990 WHERE "we two" = 'ngalbelpa'
SELECT "them two (the two)" FROM "table_15990" WHERE "we two" = 'ngalbelpa'