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Author: Amanda Butler

docs/tools/testing/testing_intro.md

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 Testing is a critical step in the development process. The Arm Mbed ecosystem offers several tools to help you test your code. 
 
-Unit testing tools can be used to build and run Mbed OS unit tests. Each unit test is built into an isolated test executable using a separate build system and build tools native to the development machine without any hardware or software dependencies. The tool can be used with Mbed CLI using the keyword `unittest`.
+You can use unit testing tools to build and run Mbed OS unit tests. Each unit test is built into an isolated test executable using a separate build system and build tools native to the development machine without any hardware or software dependencies. You can use the tool with Mbed CLI using the keyword `unittest`.
 
 Greentea, `htrun` and `mbed-ls` are testing tools written in Python. Greentea tests serve as functional unit tests in C++, as well as integration tests for complex use cases that execute on microcontrollers. The Mbed CLI tool has a verb `test` that drives these tools to form a testing system. These comprise our automated testing framework for Mbed OS development.