I want to create content in Chinese language manually in drupal 7 just by inserting translated text into body, without using any module like internationalization. Kindly suggest any solution ? Do I need to add language support for chines by using 'locale' module ?
See how to install a language on Drupal.org. After installing and enabling Chinese as a language, you will be able to specify that a node is a Chinese language node when creating/editing it.
There is no risk of data corruption, but in order to avoid problems, never change the default language (as quoted from the documentation).