"IT"

[Juan Antonio]

In this text. "Hotel Ice is made of 250 tons of ice. It takes 8 weeks to build".
The pronoun "it" substitute "the hotel" or "to build".
Does the last statement mean the same that: "It takes 8 weeks to build it".
Please, explain it.
Can I say "They take 8 hours to get home" or do I have to say "It takes 8 hours for them to get home".
Thanks a lot in advance.

[Tdol]

It takes 8 weeks to build. It = the hotel
It takes 8 weeks to build it. The first it = empty subject to make the serntence grammatical.

Of the two, the first sound better to me.

Can I say "They take 8 hours to get home" or do I have to say "It takes 8 hours for them to get home". (Or It takes them 8 hours....)

You can use both, though the second form is more common.