If it's informal, as if you're talking to a friend or peer, then you would say:
Descansa.
If it's formal, as if you're talking to a grandparent, or acquaintance, then you would say:
Descanse.
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I would add to the above answer thar the "a lot" factor is missing. So I would say "Descansa mucho" or "Descanse mucho".
To say 'I have to rest' in Spanish, you would say 'Tengo que descansar.'
To say 'I am going to rest' in Spanish, you would say 'Voy a descansar.'
Descansar
'a lot' in Spanish is 'mucho'
no mucho.
Mucho.
Leemos mucho (en espanol) = We read a lot (in Spanish)
mucho/mucha
tengo mucho
mucho
To say 'parking lot' in Spanish, you would say 'estacionamiento.' (Pronounced ess-tah-thee-ownahm-YENTaw) ('th' as in 'thin')
Hello to rest of the family = Hola a los demas/otros de la familia