を務める

serve as

→ を
phrase Uncommon #16,817
serve as Used when someone takes on or performs a particular role or responsibility.
JA: 私は式典の司会を務める。
EN: I will serve as the host of the ceremony.

彼は私たち両方のために読師を務めることはできない。

He can't serve as the reader for both of us.

彼はジョンにかわりを務めるように命じた。

He ordered John to take his place.

実験の助手を務めるグリムです

I'm Grim, the experiment's assistant.

— es[エス] (2001)

首相の留守中は外務大臣が代理を務める。

The foreign minister will serve as acting prime minister while the prime minister is away.