英语语法分析

Acknowledgment for the retransmitted packet is received.

接收到重新传输数据包的确认。

If a predefined time is exceeded, then the data should be retransmitted.

如果超过了预定义的时间，数据将被重新传输。

MSUs are the only signal units that are retransmitted if they are received in error.

MSU是信令接收出错时仅传输的信令单元。