refine the description

cmd/utils/flags.go

@@ -282,7 +282,7 @@ var (
 					   by comparing the diffhash(an identify of difflayer generated by the block) and state root.", 
 				"insecure: same as full mode, except that it can tolerate without verifying the diffhash when verify node does not have it.", 
 				"none: no merkle state root verification at all, there is no need to setup or connect remote verify node at all,
-				       it is more light comparing to full and insecure mode, but get a very little chance that the state is not consistent
+				       it is more light comparing to full and insecure mode, but get a very small chance that the state is not consistent
 						with other peers."`,
 		Value: &defaultVerifyMode,
 	}