I found the following sentence in a movie. The context is there is a boy who do not like to fly and the girl tell him the following sentence. In fact, I cannot understand the grammar associated with the following sentence. I mean, could someone please let me know why they have used "had" instead of "have" in the second half of the sentence.
I would make sure you had a good flight.
It seems correct to me as a conditional statement about a possible future event.
Were it a certainty that the flight would take place in the future, you could say:
I will make sure you have a good flight.
In your example though, there are two different things that are uncertain. Firstly, it seems the boy isn't sure sure that he will fly. Secondly, the girl is unsure that she will get the opportunity to help the boy enjoy the flight. Both are conditional on each other, because the boy wont fly without the girl's help, but the girl can't help him unless he flies.
If the boy was flying anyway, then you could say he is going to have a flight. However, he isn't certain, so the girl is speaking in terms of if he had a flight.
In fact, you could write the sentence in the third person as:
If he had a flight, she would make it a good one.
This sounds as if it was said in a situation where the boy was supposed to fly or was thinking about flying and did not fly. And the girl was reassuring him,that if he had made the decision to take the flight, she would make sure the flight was good for him.
