CONVENTION
呃哼（用于書面語中表示諷刺意味或用于引起注意）
In writing, ahem is used to show that someone is being ironic. Ahem is also used to show that someone wants to get another person's attention.
例句
It can be a dangerous course of action which might be sound in theory but — ahem — perhaps a trifle risky in practice...
這可能是一次危險的行動，在理論上聽著無縫可擊，但——呃哼——真做起來卻可能有點冒險。
It is not unknown for valuable display items to go, ahem, missing.
貴重的展品，呃哼，丟失的話，會眾人皆知。