mil ochocientos doce
they said it would last 4 years
You would say, "Tengo siete años."
The expression to say how old you are or a material object is in Spanish is "tener ____ años".If you literally want to translate "years old" into Spanish, this would be "años de vejez", but this is nonsense to any Spanish speaker.
You would say "Teresa tiene quince años."
To say 'I have a microwave' in Spanish, you would say 'Tengo una microonda.'
To say 'I have a notebook' in Spanish, you would say 'Tengo un cuaderno.'
To say 'furniture shop' in Spanish, you would say 'muebleria.'
in Spanish, you do not say that someone is so many years, but rather that he has years. So in Spanish you say "he has 68 years." "Tiene sesenta y ocho años". Normally you would not use the personal pronoun, since the conjugated verb already carries that information.
To say 'rich' in Spanish, you would say 'rico.'
To say 'knives' in Spanish, you would say 'cuchillos.'
To say 'condensation' in Spanish, you would say 'condensación.'
To say 'evaporation' in Spanish, you would say 'evaporación.'