Usages of lamentar
Lamento que no conozcas a mi familia.
I regret that you do not know my family.
Lamentan que yo no traiga el coche al viaje.
They regret that I am not bringing the car on the trip.
El experto, el cual está aquí, lamenta no haber explicado la teoría.
The expert, who is here, regrets not having explained the theory.
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