Quick check

Hi,
can someone check if this text is correct:

Construction:

The application has 3 main layer. The first and the lowest is written in C, to speed up very complex calculation. By wrapper first layer communicate with Java layer which is the second level of application responsible for the desktop application. The highest level of application is written in Java EE and this is the web application level. Application has about 4-4.5 mln. lines of the code.

Thanks