The sentries at the barracks are replaced

[Bassim]

I do not know what word to use when, for example, the sentries replace each other.
Would this sentence be correct?
The sentries at the barracks are replaced every two hours.

But then the question is how to describe the moment when they are replaced.
For example, would the following sentence be correct? I have to say I feel that my sentence is not correct.

The attack happened during the exchange of the sentries.

 

[teechar]

The sentries (guards?) at the barracks [STRIKE]are replaced[/STRIKE] change duty every two hours.


The attack happened during the changing of the guard. [STRIKE]exchange of the sentries.[/STRIKE]

You could also use "changeover" instead of "changing of the guard."

 

[Bassim]

Thank you teechar,
I was asking this question because I could not find the proper word regarding the change of guards in my dictionaries.

I am wondering if the following sentence would be correct.

We had to wait for a while at the bus station until the drivers changed.

 

[teechar]

We had to wait for a while at the bus station for the changeover of [STRIKE]until the[/STRIKE] drivers. [STRIKE]changed.[/STRIKE]

.

 

[emsr2d2]

"The Changing of the Guard" is a set phrase in the UK when used to refer to an event that happens at Buckingham Palace.