Here’s a suitable completion for the passage with prepositions:

Last year my family went (1) **on** holiday to Thailand. We went (2) **by** air; it was a very long journey, but we were very well looked after (3) **on** the plane by all the stewardesses. When we arrived (4) **at** the airport, we went directly to our hotel (5) **by** taxi. There was a lot of traffic (6) **on** the streets of the city, and there were many people walking (7) **on** the pavements. We stayed (8) **in** a large hotel (9) **on** the outskirts of Bangkok. We were given a wonderful suite (10) **on** the top floor of the hotel. The most enjoyable day I had was when we went (11) **on** a trip (12) **by** boat down the river to the crocodile farm. We had a wonderful holiday!