"¿Puedes mantener esto?"
Translation:Can you keep this?
Your problem here is English not Spanish. «Keep» has so many uses in English that are translatable by many different unrelated words in Spanish. A keep as a noun can be a jail or a fortified space. To keep a job would be guardar (or mantener if it's a question of keeping UP to the responsibilities). It can be sostener if it means keeping up a jogging speed or an amount of work. It can be mantener if it's a question of keeping up with expenses or being able to afford a house, a car, a wife. It could be conservar (un mueble histórico), tener (una farmacia tiene muchos medicamentos), or keep someone guessing tener a alguien en ascuas, llevar o escribir (un diario), hacer esperar=keep waiting), cumplir (una promesa), acercarse [no me acerques=keep away], guardar +++many more. The most useful (for me anyway) is seguir + gerund.....Sigo trabajando, sigo cantando, sigo viviendo en la misma casa, sigo estudiando, sigo siendo policía. There was a telenovela called "Te sigo amando"= ???
I got credit for "Can you keep this up?", but DuoLingo suggested another translation was " Can you keep this?". The former English version implies maintaining a task or level of activity, while the latter implies posession of an object. Can matener be used that way?