Just a point from a British English perspective: The rule about using 'ride' only to refer to bicycles, motorbikes and horses so on does in fact hold good for British English. In GB Eng you ride animals and two-wheeled vehicles. We are familiar with phrases such as 'ride the bus' or 'ride the subway' from American media, but we don't use these expressions in GB English. We'd say 'go by bus' 'go on the bus' 'travel by bus' or 'take a bus'. I wonder if your teachers or coursebook is based on British English?

Yes... "to ride" can be something like a horse or bicycle but it can also be a larger transport vehicle such as a bus, a subway or an airplane. Here's a little extra tidbit: there is an expression in the United States "to ride the rails" which means to travel by train, especially when done by vagabonds who hitch a ride on a freight train. There are many other meanings of "to ride" which are metaphorical and don't actually have anything to do with a person using a vehicle to get somewhere. If you're interested, message me and I'll go into more detail.

I'm American...I would understand if you rode a bus or a train, but I would think it was very strange if you said you "rode a ship," or an airplane. Personally, I wouldn't use "ride" with any of those, I would say "take" with almost any means of transportation: I took a bus, took a ferry, took a train, took the subway, took a plane, took the monorail, took the elevator.

The others are right - you can ride just about anything! Ride trams, ride camels, ride the rails, ride a roller-coaster. Ships ride the waves, and we can ride (out) the storm. We can also ride high, ride down, ride herd, and things like very short skirts can ride up (embarrassing!) Richard S from the US of A suggests you message him for many more. That's a good idea if you are really interested.

We use "ride" with almost anything that can take us from one point to another. Ride a bus. Ride the subway. Ride an elevator. Ride the escalator. :)