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diff --git a/usecases/understand-sidecar-injection-and-traffic-hijack-in-istio-service-mesh.md b/usecases/understand-sidecar-injection-and-traffic-hijack-in-istio-service-mesh.md
index 9f7e95a7c..3811fcde1 100644
--- a/usecases/understand-sidecar-injection-and-traffic-hijack-in-istio-service-mesh.md
+++ b/usecases/understand-sidecar-injection-and-traffic-hijack-in-istio-service-mesh.md
@@ -1,4 +1,4 @@
-# 深入理解Istio Service Mesh中的Envoy Sidecar注入与流量劫持
+# Sidecar 的注入与流量劫持
 
 **本文基于 Istio 1.5。**