Dave's ESL Cafe's Student Discussion Forums

[dido4]

There are two people in a picture. Each is riding a bike. There are two bikes, and they are riding their own bikes.

The question is:
Can they ride a bike?
The answer is:
Yes, they can ride a bike.

Q1:Isn't it:
They can ride bikes.
Why is "ride a bike"? There are two people there. Don't know why. The answer is singular not plural?

[Suzanne]

Hello!

I can see why you might be confused. Let me see if I can help.
"Ride a bike" is a phrase (a collocation) that is used as a single unit.
We use it, no matter if the suject is singular or plural. When talking about more than one person, there is an assumed "each" in the sentence.
Examples:
"John and Mary [each] learned to ride a bike when they were five years old."
"Mr. and Mrs. Smith are 80 years old, and [each] can still ride a bike, just like when they were younger."
"It's fun to ride a bike in Bruges."

"Ride bikes" is a little different. This is more of an activity.
Examples:
"Let's ride bikes to the store." or "Let's ride our bikes to the store."
"John and Mary rode bikes into town to save on gas."

Here's a sentence with both:
"After Peggy and I learned to ride a bike, we would often ride bikes to get ice cream."

I hope this helps--it is a great question!