diff --git a/core/blockchain.go b/core/blockchain.go
index 5c1e08592..1880d8401 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -1367,7 +1367,8 @@ func (bc *BlockChain) writeBlockAndSetHead(block *types.Block, receipts []*types
 		bc.writeHeadBlock(block)
 	}
 	bc.futureBlocks.Remove(block.Hash())
-
+	
+	// ptd and externTd are both PluGeth injections
 	ptd := bc.GetTd(block.ParentHash(), block.NumberU64()-1)
 	if ptd == nil {
 		return NonStatTy, consensus.ErrUnknownAncestor
diff --git a/core/rawdb/freezer_batch.go b/core/rawdb/freezer_batch.go
index df9ffa30f..99d226e9a 100644
--- a/core/rawdb/freezer_batch.go
+++ b/core/rawdb/freezer_batch.go
@@ -44,13 +44,17 @@ func newFreezerBatch(f *Freezer) *freezerBatch {
 
 // Append adds an RLP-encoded item of the given kind.
 func (batch *freezerBatch) Append(kind string, num uint64, item interface{}) error {
+	// begin PluGeth injection
 	PluginTrackUpdate(num, kind, item)
+	// end PluGeth injection
 	return batch.tables[kind].Append(num, item)
 }
 
 // AppendRaw adds an item of the given kind.
 func (batch *freezerBatch) AppendRaw(kind string, num uint64, item []byte) error {
+	// being PluGeth injection
 	PluginTrackUpdate(num, kind, item)
+	// end PluGeth injection
 	return batch.tables[kind].AppendRaw(num, item)
 }
 
diff --git a/eth/tracers/api.go b/eth/tracers/api.go
index df55a298d..0fd1983b7 100644
--- a/eth/tracers/api.go
+++ b/eth/tracers/api.go
@@ -886,7 +886,6 @@ func (api *API) traceTx(ctx context.Context, message core.Message, txctx *Contex
 		// Get the tracer from the plugin loader
 		//begin PluGeth code injection
 		if tr, ok := getPluginTracer(*config.Tracer); ok {
-			//end PluGeth code injection
 			tracer = tr(statedb, vmctx)
 		} else {
 			tracer, err = New(*config.Tracer, txctx, config.TracerConfig)
@@ -894,6 +893,7 @@ func (api *API) traceTx(ctx context.Context, message core.Message, txctx *Contex
 				return nil, err
 			}
 		}
+		// end PluGeth injection
 	}
 	// Define a meaningful timeout of a single transaction trace
 	if config.Timeout != nil {