Updated EN_KCP Feature (markdown)

EN_KCP-Feature.md

@@ -8,19 +8,19 @@ TCP is design to transmit as most data as possible over internet, but maybe not
 
 #### Retransmit All or Partial
 
-   TCP丢包时会全部重传从丢的那个包开始以后的数据，KCP是选择性重传，只重传真正丢失的数据包。
+   When retransmission packets, TCP will retransmit the whole packet, while KCP only the dropped part of packet.
 
-#### 快速重传：
+#### Fast Retransmission
 
-   发送端发送了1,2,3,4,5几个包，然后收到远端的ACK: 1, 3, 4, 5，当收到ACK3时，KCP知道2被跳过1次，收到ACK4时，知道2被跳过了2次，此时可以认为2号丢失，不用等超时，直接重传2号包，大大改善了丢包时的传输速度。
+   For example, the sender has sent packets 1,2,3,4,5, then got the ACK message from peer 1,3,4,5. When got ACK 1,3, KCP will notice the packet 2 maybe dropped; when got ACK 1,3,4, the packet 2 almost dropped and KCP will directly retransmit packet 2 without wait for timeout. This algorithm can improve the transport speed when network is not very good and dropping some packets.
 
-#### 延迟ACK vs 非延迟ACK：
+#### Delay ACK or Realtime
 
-   TCP为了充分利用带宽，延迟发送ACK（NODELAY都没用），这样超时计算会算出较大 RTT时间，延长了丢包时的判断过程。KCP的ACK是否延迟发送可以调节。
+   As TCP designed to send more data over network, it will delay to send ACK, even though set TCP_NODELAY. This algorithm will increase the RTT and need more time to determine whether packets dropped or not. To avoid this, KCP allows realtime ACK without delay.
 
 #### UNA vs ACK+UNA：
 
-   ARQ模型响应有两种，UNA（此编号前所有包已收到，如TCP）和ACK（该编号包已收到），光用UNA将导致全部重传，光用ACK则丢失成本太高，以往协议都是二选其一，而 KCP协议中，除去单独的 ACK包外，所有包都有UNA信息。
+   ARQ(Automatic Repeat reQuest) includes UNA and ACK responding mode. UNA specifies the last completely series(group) of received packet number, while ACK specifies the received packet number; when use UNA, all packets will retransmit the whole group when any packet dropped; when use ACK, it cost a lot when packets dropped. Other protocols use either UNA or ARQ, but KCP use a mix model of UNA and ACK, each packet contains UNA and there is also ACK packets.
 
 #### 非退让流控：