The key to exercise solutions in chapter Unit 20 - I'm going to (do) for the textbook English Grammar in Use with authors Raymond Murphy from Cambridge University Press
Question
What is going to happen in these situations? Use the words in brackets.
Answer
It's going to rain.
He's going to be late.
The boat is going to sink.
They're going to run out of petrol.
It's going to cost a lot (of money) to repair the car.