Hydro Thunder Hurricane

You must get all gold trophies in the single player game. Just keep practicing and use novice boats on races and gauntlet events to help you achieve your goal. Some events can only be done on Pro and Expert and will take most of your time and will take quite a bit of patience to complete and yes, lots of practicing. The difficulty spike from Novice to Expert is pretty big so keep at it until you make it.

There are 4 different kinds of events:
Races: These are pretty easy to get gold on. Just use the boat "Vector" and boost a lot and you should have few problems.

Ring Master: These are some of the hardest challenges in the game. The novice ones are easy but once you get to expert, you will have a heck of a time getting first place.

Here are some video guides to help with getting gold on the Expert Ring Master challenges.

Gauntlet: Get the best possible time and try not to hit any barrels because that will take off some precious time. Leave a little bit of boost so you can jump over any at the last second if you need too. Place these with a novice boat and you should have few problems.

Championship: The novice Championships should be easy like the normal races and other events but things will get tough when you get to the expert championships. Just keep practicing and remember where all the boost cans are at and you can get this. Do all other events before you attempt the expert championships because they are a mixture of the other 3 modes and the game can be pretty unforgiving in expert mode.
Also, in the championships, you do not need first place in every round. It will help tremendously but if you can only pull a 2nd place off in an expert event, keep going and if you get first in the others you should get first place overall in the end.