Need English to Sanskrit translation help (messed up first post)

Need help translating these quotes into Sanskrit if possible. The free translation sites are doing the job. Thanks in advance.

The only real failure in life is not to be true to the best one knows

Do not dwell in the past, do not dream of the future, concentrate the mind on the present moment.

No one saves us but ourselves. No one can and no one may. We ourselves must walk the path.