N1
を兼ねて
And also, Also (partly) to, Also (partly) for (the purpose of), At the same time, To double as, When … also, While … as well, And as
予行
練習
を
兼ね
て
While also serving as a rehearsal ~ and doing so for the purpose of rehearsing beforehand.
And also, Also (partly) to, Also (partly) for (the purpose of), At the same time, To double as, When … also, While … as well, And as