Verb conjugation of "mantener" in Spanish

Do you think it would be good to put a regional box near each translation [optional of course]? That means a translator can check countries if it is only used there. Regional differences appear in all languages.
Productivity declines when it is too hot outside. Oscar therefore closed his laptop and production unit and headed towards the lake where his pretty girlfriend was waiting for him. Once he arrived he bought a ice cream as a surprise.
It's very good that you can learn English with the help of technology (Internet), I think you'll learn quickly. Although I am now getting better, I feel the improvement. But once again I lack vocabulary.