Build failed

When I tried to build project, i got this error:

/home/ns/Android/sdk/tools/ant/build.xml:720: The following error occurred while executing this line:
/home/ns/Android/sdk/tools/ant/build.xml:734: Compile failed; see the compiler error output for details.

Some advice?

Can you provide some more detail? It’s a bit hard to help find a solution with just that. What version of cordova do you have installed? Is there any log error files?