I'd like you to check these other sentences please. Thank you very much.

1)The train is going to take eight hours to get to Rome.
2) The train journey is going to last eight hours.
3) We are flying back to Milan on 12 July. Our parents are going to pick us up at Milan airport.
4) On/for my summer holiday I'm going to go on a two-day trip in the mountains with my parents.
5) We are going to go on a car sightseeing tour of Rome.
In the following morning we are going to visit the Colosseum.
6) We are going to sleep in a tent and to eat in a typical restaurant.
It's going to be a fantastic holiday.
I'm going on a two-week holiday (at the seaside).

#5. On the following...

All the rest is fine.

1) "The train is going to take eight hours to get to Rome." - This sentence states that it will take eight hours for the train to reach Rome. To check the sentence, you can start by verifying if the tense and verb usage are correct. In this case, the sentence uses the present continuous "is going to take," which is appropriate for talking about future plans. Additionally, you can check if the time duration (eight hours) makes sense in the given context.

2) "The train journey is going to last eight hours." - This sentence indicates that the train journey will span over a period of eight hours. To check it, you can ensure that the verb tense and the sentence structure are correct. In this case, the sentence uses the present continuous "is going to last," which works well for discussing future events. Also, you can verify if the duration of eight hours is suitable for a train journey.

3) "We are flying back to Milan on 12 July. Our parents are going to pick us up at Milan airport." - This sentence mentions a flight back to Milan on a specific date and that the parents will be there to receive them at the airport. To check it, you can review if the verb tenses are appropriate. In this case, the present continuous tense "are flying" and "are going to pick" are used, which fit well for discussing future plans. Moreover, you can ensure that the date mentioned (12 July) and the arrangement with the parents make sense in the given context.

4) "On/for my summer holiday, I'm going to go on a two-day trip in the mountains with my parents." - This sentence expresses the plan to embark on a two-day trip in the mountains during the summer holiday. To check it, you can assess the verb tense and sentence structure. In this case, the present continuous "I'm going to go" is used to talk about future intentions. Additionally, you can consider whether the idea of a two-day trip in the mountains aligns with the concept of a summer holiday.

5) "We are going to go on a car sightseeing tour of Rome. In the following morning, we are going to visit the Colosseum." - This sentence states the intention of taking a car sightseeing tour in Rome and then visiting the Colosseum the next morning. To check it, you can examine the verb tenses and sentence structure. The present continuous "are going to go" and "are going to visit" are utilized correctly to discuss future plans. Furthermore, you can verify if the sequence of events, such as the sightseeing tour followed by the visit to the Colosseum, is logical.

6) "We are going to sleep in a tent and to eat in a typical restaurant. It's going to be a fantastic holiday." - This sentence describes the plan to sleep in a tent and dine at a typical restaurant during a holiday, with the expectation that it will be fantastic. To check it, you can confirm that the verb tenses and sentence structure are correct. The present continuous "are going to sleep" and "are going to eat" are used properly for discussing future arrangements. Additionally, you can evaluate if the notion of sleeping in a tent, eating at a typical restaurant, and the overall expectation of a fantastic holiday are consistent and coherent.

"I'm going on a two-week holiday (at the seaside)." - This sentence indicates that the speaker is planning to go on a two-week holiday by the seaside. To check it, you can review the verb tense and sentence structure. In this case, the present continuous "I'm going" is used accurately to convey a future plan. Furthermore, verify if the duration of two weeks and the seaside destination align with the context and intention of the sentence.