second-in-command

1. N-SING A second-in-command is someone who is next in rank to the leader of a group, and who has authority to give orders when the leader is not there. 副指揮

He was posted to Hong Kong as second-in-command of C Squadron. 他被派到香港任C中隊(duì)的副隊(duì)長(zhǎng)。