diff --git a/CMakeLists.txt b/CMakeLists.txt
index 22d007a..2ef91a7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -5,6 +5,7 @@ set(CMAKE_C_STANDARD 23)
 set(CMAKE_C_STANDARD_REQUIRED TRUE)
 
 add_subdirectory(test_1_1)
+add_subdirectory(test_1_2)
 add_subdirectory(test_2_1)
 add_subdirectory(test_final)
 add_subdirectory(test_final_1)
diff --git a/test_1_2/CMakeLists.txt b/test_1_2/CMakeLists.txt
new file mode 100644
index 0000000..ae5aed0
--- /dev/null
+++ b/test_1_2/CMakeLists.txt
@@ -0,0 +1,5 @@
+project(test_1_2)
+
+set(testName "${PROJECT_NAME}")
+
+add_subdirectory(task_3)
diff --git a/test_1_2/task_3/CMakeLists.txt b/test_1_2/task_3/CMakeLists.txt
new file mode 100644
index 0000000..c62c971
--- /dev/null
+++ b/test_1_2/task_3/CMakeLists.txt
@@ -0,0 +1,6 @@
+project("${testName}_task_3")
+
+add_library(commentsExtractor commentsExtractor.c)
+
+add_executable(${PROJECT_NAME}_test test.c)
+target_link_libraries(${PROJECT_NAME}_test commentsExtractor)
diff --git a/test_1_2/task_3/commentsExtractor.c b/test_1_2/task_3/commentsExtractor.c
new file mode 100644
index 0000000..4a2d0ab
--- /dev/null
+++ b/test_1_2/task_3/commentsExtractor.c
@@ -0,0 +1,33 @@
+#include "commentsExtractor.h"
+
+#include <stdbool.h>
+#include <stdio.h>
+
+bool extractSemicolonComments(FILE *input, FILE *output) {
+    if (input == NULL || output == NULL) {
+        return false;
+    }
+
+    bool isComment = false;
+    while (!feof(input)) {
+        int readCharacter = fgetc(input);
+        if (readCharacter == EOF) {
+            break;
+        }
+
+        if (readCharacter == ';') {
+            isComment = true;
+        } else if (readCharacter == '\n') {
+            if (isComment) {
+                fputc('\n', output);
+            }
+            isComment = false;
+        }
+
+        if (isComment) {
+            fputc(readCharacter, output);
+        }
+    }
+
+    return true;
+}
diff --git a/test_1_2/task_3/commentsExtractor.h b/test_1_2/task_3/commentsExtractor.h
new file mode 100644
index 0000000..4f3b47b
--- /dev/null
+++ b/test_1_2/task_3/commentsExtractor.h
@@ -0,0 +1,10 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stdio.h>
+
+/// @brief Reads from file all comments starting with `;` and ending with '\n'
+/// @param input File to read comments from
+/// @param output File to write comments to
+/// @return `true` if extracted comments successfully, `false` otherwise (some of files were `NULL`)
+bool extractSemicolonComments(FILE *input, FILE *output);
diff --git a/test_1_2/task_3/test.c b/test_1_2/task_3/test.c
new file mode 100644
index 0000000..74f5b29
--- /dev/null
+++ b/test_1_2/task_3/test.c
@@ -0,0 +1,65 @@
+#define CTEST_MAIN
+#define CTEST_SEGFAULT
+#include "../../ctest/ctest.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "commentsExtractor.h"
+
+#define TEST_FILES "testFiles/"
+#define INPUT "_input.txt"
+#define OUTPUT "_output.txt"
+
+int main(int argc, const char *argv[]) {
+    return ctest_main(argc, argv);
+}
+
+static void testCase(const char *inputFilename, const char *expectedResultFilename) {
+    const char *outputFilename = "testOutputFile.txt";
+
+    FILE *inputRead = fopen(inputFilename, "r");
+    ASSERT_NOT_NULL(inputRead);
+
+    FILE *outputWrite = fopen(outputFilename, "w");
+    ASSERT_NOT_NULL(outputWrite);
+
+    ASSERT_TRUE(extractSemicolonComments(inputRead, outputWrite));
+
+    ASSERT_EQUAL(fclose(inputRead), 0);
+    ASSERT_EQUAL(fclose(outputWrite), 0);
+
+    FILE *realOutputRead = fopen(outputFilename, "r");
+    ASSERT_NOT_NULL(realOutputRead);
+
+    FILE *expectedOutputRead = fopen(expectedResultFilename, "r");
+    ASSERT_NOT_NULL(expectedOutputRead);
+
+    while (!feof(realOutputRead)) {
+        int realReadResult = fgetc(realOutputRead);
+        int expectedReadResult = fgetc(expectedOutputRead);
+
+        ASSERT_EQUAL(realReadResult, expectedReadResult);
+
+        if (realReadResult == EOF) {
+            break;
+        }
+    }
+
+    ASSERT_EQUAL(fclose(realOutputRead), 0);
+    ASSERT_EQUAL(fclose(expectedOutputRead), 0);
+
+    ASSERT_EQUAL(remove(outputFilename), 0);
+}
+
+CTEST(commentExtractorTests, singleCommentTest) {
+    testCase(
+        TEST_FILES "singleComment" INPUT,
+        TEST_FILES "singleComment" OUTPUT);
+}
+
+CTEST(commentExtractorTests, severalCommentsTest) {
+    testCase(
+        TEST_FILES "severalComments" INPUT,
+        TEST_FILES "severalComments" OUTPUT);
+}
diff --git a/test_1_2/task_3/testFiles/severalComments_input.txt b/test_1_2/task_3/testFiles/severalComments_input.txt
new file mode 100644
index 0000000..38e2fff
--- /dev/null
+++ b/test_1_2/task_3/testFiles/severalComments_input.txt
@@ -0,0 +1,5 @@
+
+123456789 ; qwertyuiop ; asdfghjkl ; zxcvbnm
+; aaaaaaaa
+qwezxc
+012345;6789
diff --git a/test_1_2/task_3/testFiles/severalComments_output.txt b/test_1_2/task_3/testFiles/severalComments_output.txt
new file mode 100644
index 0000000..6453a91
--- /dev/null
+++ b/test_1_2/task_3/testFiles/severalComments_output.txt
@@ -0,0 +1,3 @@
+; qwertyuiop ; asdfghjkl ; zxcvbnm
+; aaaaaaaa
+;6789
diff --git a/test_1_2/task_3/testFiles/singleComment_input.txt b/test_1_2/task_3/testFiles/singleComment_input.txt
new file mode 100644
index 0000000..12a7e7b
--- /dev/null
+++ b/test_1_2/task_3/testFiles/singleComment_input.txt
@@ -0,0 +1 @@
+gwfhygefgehfg;sdfersfyergfyryerfer
diff --git a/test_1_2/task_3/testFiles/singleComment_output.txt b/test_1_2/task_3/testFiles/singleComment_output.txt
new file mode 100644
index 0000000..eb0659f
--- /dev/null
+++ b/test_1_2/task_3/testFiles/singleComment_output.txt
@@ -0,0 +1 @@
+;sdfersfyergfyryerfer