Used for acknowledgements or flow control.

用于应答或流控制。

Guaranteed delivery with optional acknowledgements.

带有可选回执有保证的运送。

Users receive multiple acknowledgements for the same message.

用户收到同一消息的多个确认。

TCP controls the flow of data based on packet acknowledgements from the peer endpoint.

TCP基于数据包确认从对等端点控制数据流。

Acknowledgements and any additional information concerning research grants, etc.

认知与任何进一步的资料，作为研究补助金，等等。