Generalmente duermo cinco horas. choices: - con - de - para - por

Generalmente duermo cinco horas.

Translation:

Generally, I sleep [blank] five hours.

The options

As con and de don't work in this context, we have to choose between para and por. Both mean "for" but they are used in different situations. Para is used to speak about objectives (among other things), and por is used to talk about duration (also among other things).

Five hours is the amount of time you sleep, i.e. the duration of your sleep, therefore the answer is por.

por

Generalmente duermo por cinco horas.

Generally I sleep ___ five hours.

Generalmente duermo (por) cinco horas.

Correct option: D) Por.

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