1.

This is her first visit to Iguazu Falls in Argentina.

not

She    Iguazu Falls in Argentina before.   

2.

My neighbour came to live here ten years ago.

for

My neighbour    ten years.

3.

I don't advise you to rent a flat in that part of town.

better

You    a flat in that part of town.

4.

I think the best thing you can do is stay in a cheap hotel.

you

If I    in a cheap hotel.

5.

The cost of living in Madrid is much higher than in Buenos Aires.

nearly

The cost of living in Buenos Aires is    in Madrid.

6.

It's ages since I last saw Alberto.

not

I    ages.

7.

They haven't painted the town hall since 1991.

last

The town hall    1991.

8.

I haven't lived in such a friendly neighbourhood before.

time

This is the    in such a friendly neighbourhood.

9.

Elisa won't buy that house because the roof leaks.

leak

If the roof    buy that house.

10.

In the past Francisco drove to work, but he doesn't any more.

used

Francisco    to work.