diff --git a/runtime/engine/common/utils/blank_process.cc b/runtime/engine/common/utils/blank_process.cc
deleted file mode 100644
index d45eefcdb..000000000
--- a/runtime/engine/common/utils/blank_process.cc
+++ /dev/null
@@ -1,26 +0,0 @@
-#include "utils/blank_process.h"
-
-namespace ppspeech {
-
-std::string RemoveBlk(const std::string& str) {
-    std::string out = "";
-    int ptr_in = 0;    //  the pointer of input string (for traversal)
-    int end = str.size();
-    int ptr_out = -1;  //  the pointer of output string (last char)
-    while (ptr_in != end) {
-        while (ptr_in != end && str[ptr_in] == ' ') {
-            ptr_in += 1;
-        }
-        if (ptr_in == end) 
-            return out;
-        if (ptr_out != -1 && isalpha(str[ptr_in]) && isalpha(str[ptr_out]) && str[ptr_in-1] == ' ')
-            // add a space when the last and current chars are in English and there have space(s) between them
-            out += ' ';
-        out += str[ptr_in];
-        ptr_out = ptr_in;
-        ptr_in += 1;
-    }
-    return out;
-}
-
-}  // namespace ppspeech
\ No newline at end of file
diff --git a/runtime/engine/common/utils/blank_process.h b/runtime/engine/common/utils/blank_process.h
deleted file mode 100644
index 84952651b..000000000
--- a/runtime/engine/common/utils/blank_process.h
+++ /dev/null
@@ -1,9 +0,0 @@
-#include <string>
-#include <vector>
-#include <cctype>
-
-namespace ppspeech {
-
-std::string BlankProcess(const std::string& str);
-
-}  // namespace ppspeech
\ No newline at end of file
diff --git a/runtime/engine/common/utils/blank_process_test.cc b/runtime/engine/common/utils/blank_process_test.cc
deleted file mode 100644
index 75f762ae6..000000000
--- a/runtime/engine/common/utils/blank_process_test.cc
+++ /dev/null
@@ -1,26 +0,0 @@
-#include "utils/blank_process.h"
-
-#include <gtest/gtest.h>
-#include <gmock/gmock.h>
-
-TEST(BlankProcess, BlankProcessTest) {
-    std::string test_str = "我 今天 去 了 超市 花了 120 元。";
-    std::string out_str = ppspeech::BlankProcess(test_str);
-    int ret = out_str.compare("我今天去了超市花了120元。");
-    EXPECT_EQ(ret, 0);
-
-    test_str = "how are you today";
-    out_str = ppspeech::BlankProcess(test_str);
-    ret = out_str.compare("how are you today");
-    EXPECT_EQ(ret, 0);
-
-    test_str = "我 的 paper 在 哪里？";
-    out_str = ppspeech::BlankProcess(test_str);
-    ret = out_str.compare("我的paper在哪里？");
-    EXPECT_EQ(ret, 0);
-
-    test_str = "我 今天     去 了 超市     花了   120 元。";
-    out_str = ppspeech::BlankProcess(test_str);
-    ret = out_str.compare("我今天去了超市花了120元。");
-    EXPECT_EQ(ret, 0);
-}
\ No newline at end of file
diff --git a/runtime/engine/common/utils/text_process.cc b/runtime/engine/common/utils/text_process.cc
new file mode 100644
index 000000000..bcaffd7ae
--- /dev/null
+++ b/runtime/engine/common/utils/text_process.cc
@@ -0,0 +1,77 @@
+#include "utils/text_process.h"
+
+namespace ppspeech {
+
+std::string RemoveBlk(const std::string& str) {
+    std::string out = "";
+    int ptr_in = 0;    //  the pointer of input string (for traversal)
+    int end = str.size();
+    int ptr_out = -1;  //  the pointer of output string (last char)
+    while (ptr_in != end) {
+        while (ptr_in != end && str[ptr_in] == ' ') {
+            ptr_in += 1;
+        }
+        if (ptr_in == end) 
+            return out;
+        if (ptr_out != -1 && isalpha(str[ptr_in]) && isalpha(str[ptr_out]) && str[ptr_in-1] == ' ')
+            // add a space when the last and current chars are in English and there have space(s) between them
+            out += ' ';
+        out += str[ptr_in];
+        ptr_out = ptr_in;
+        ptr_in += 1;
+    }
+    return out;
+}
+
+std::string AddBlk(const std::string& str) {
+    std::string out = "";
+    int ptr = 0;  // the pointer of the input string
+    int end = str.size();
+    while (ptr != end) {
+        if (isalpha(str[ptr])) {
+            if (ptr == 0 or str[ptr-1] != ' ')
+                out += " ";  // add pre-space for an English word
+            while (isalpha(str[ptr])) {
+                out += str[ptr];
+                ptr += 1;
+            }
+            out += " ";  // add post-space for an English word
+        } else {
+            out += str[ptr];
+            ptr += 1;
+        }
+    }
+    return out;
+}
+
+std::string ReverseFrac(const std::string& str, 
+                        const std::string& left_tag, 
+                        const std::string& right_tag) {
+    std::string out = "";
+    int ptr = 0;   // the pointer of the input string
+    int end = str.size();
+    int left, right, frac;  // the start index of the left tag, right tag and '/'.
+    left = right = frac = 0;
+    int len_left_tag = left_tag.size();
+    int len_right_tag = right_tag.size();
+
+    while (ptr != end) {
+        // find the position of left tag, right tag and '/'. (xxx<tag>num1/num2</tag>)
+        left = str.find(left_tag, ptr);
+        if (left == -1)
+            break;
+        out += str.substr(ptr, left - ptr);  // content before left tag (xxx)
+        frac = str.find("/", left);
+        right = str.find(right_tag, frac);
+        
+        out += str.substr(frac + 1, right - frac - 1) + '/' + 
+               str.substr(left + len_left_tag, frac - left - len_left_tag);  // num2/num1
+        ptr = right + len_right_tag;
+    }
+    if (ptr != end) {
+        out += str.substr(ptr, end - right - len_right_tag);
+    }
+    return out;
+}
+
+}  // namespace ppspeech
\ No newline at end of file
diff --git a/runtime/engine/common/utils/text_process.h b/runtime/engine/common/utils/text_process.h
new file mode 100644
index 000000000..e084794a5
--- /dev/null
+++ b/runtime/engine/common/utils/text_process.h
@@ -0,0 +1,15 @@
+#include <string>
+#include <vector>
+#include <cctype>
+
+namespace ppspeech {
+
+std::string RemoveBlk(const std::string& str);
+
+std::string AddBlk(const std::string& str);
+
+std::string ReverseFrac(const std::string& str, 
+                        const std::string& left_tag = "<tag>", 
+                        const std::string& right_tag = "</tag>");
+
+}  // namespace ppspeech
\ No newline at end of file
diff --git a/runtime/engine/common/utils/text_process_test.cc b/runtime/engine/common/utils/text_process_test.cc
new file mode 100644
index 000000000..3e36ca0d1
--- /dev/null
+++ b/runtime/engine/common/utils/text_process_test.cc
@@ -0,0 +1,45 @@
+#include "utils/text_process.h"
+
+#include <gtest/gtest.h>
+#include <gmock/gmock.h>
+
+TEST(TextProcess, RemoveBlkTest) {
+    std::string test_str = "我 今天     去 了 超市     花了   120 元。";
+    std::string out_str = ppspeech::RemoveBlk(test_str);
+    int ret = out_str.compare("我今天去了超市花了120元。");
+    EXPECT_EQ(ret, 0);
+
+    test_str = "how are you today";
+    out_str = ppspeech::RemoveBlk(test_str);
+    ret = out_str.compare("how are you today");
+    EXPECT_EQ(ret, 0);
+
+    test_str = "我 的 paper 在 哪里？";
+    out_str = ppspeech::RemoveBlk(test_str);
+    ret = out_str.compare("我的paper在哪里？");
+    EXPECT_EQ(ret, 0);
+}
+
+TEST(TextProcess, AddBlkTest) {
+    std::string test_str = "how are you";
+    std::string out_str = ppspeech::AddBlk(test_str);
+    int ret = out_str.compare(" how  are  you ");
+    EXPECT_EQ(ret, 0);
+
+    test_str = "欢迎来到China。";
+    out_str = ppspeech::AddBlk(test_str);
+    ret = out_str.compare("欢迎来到 China 。");
+    EXPECT_EQ(ret, 0);
+}
+
+TEST(TextProcess, ReverseFracTest) {
+    std::string test_str = "<tag>3/1</tag>";
+    std::string out_str = ppspeech::ReverseFrac(test_str);
+    int ret = out_str.compare("1/3");
+    EXPECT_EQ(ret, 0);
+
+    test_str = "<tag>3/1</tag> <tag>100/10000</tag>";
+    out_str = ppspeech::ReverseFrac(test_str);
+    ret = out_str.compare("1/3 10000/100");
+    EXPECT_EQ(ret, 0);
+}
\ No newline at end of file