Usages of mantener
No negocies con personas que te ofrecen algo sospechoso, mantén precaución.
Do not negotiate with people who offer you something suspicious; maintain caution.
Mi tutora quiere que mantenga un nivel alto de concentración.
My tutor wants me to maintain a high level of concentration.
Lo importante es mantener la calma.
The important thing is to stay calm.
Cuando estudio, intento mantener una postura cómoda en la silla.
When I study, I try to maintain a comfortable posture on the chair.
Apago el celular para mantener la concentración durante la clase.
I turn off my cell phone to maintain concentration during class.
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