how to describe/what is it called

Either one of the 1st 2 choices

Any of those would do. I'd probably say "on speaker phone".

You don't think "speaker mode" or especially "loudspeaker" sounds dated?

Not particularly. (but I'll never see 29 again!)

The meaning is clear, and the request informal. I'm wondering why anyone would say that...surely a matter for the listener/recipient? Okay yes, it might be useful sometimes.

I've said it when there are other people in the room that I want to hear what I'm saying.

I don't know, maybe it's Brit vs USA thing. Including the word mode seems superfluous at this time. Saying loudspeaker would be downright funny I think. Almost like you couldn't think of the right word.

It's been a long time since I've seen 29 also.

Fine.

Everyone understands "speakerphone", I suppose? That's the one that springs to mind.

Thank you~

When a passenger wants to get off the bus, before the stop, he has to press a certain button, and then a light, red, on a board above the drive will light up; is there a succinct term to refer to the action?:

-Passengers have to __ before alighting.

Passengers have to request a stop . . . our local public transit system has a lighted display above the driveer which reads: "Stop Requested." It might differ in other systems.

Above the driver.

British people still say "ring the bell"! (although there's no bell any more)

At 1:44 in this video-- http://www.youtube.com/watch?v=rkpvON6IpNs you will hear that the American phrase is the same as McT notes it is in England. The phrase is included in a clip of the best American comedy since Sid Caesar's Your Show of Shows. It is worth the 15 second commercial to see the clip.

Indeed, or they might say "press the stop button", or call out "Next stop, driver!", at least they do in Bristol. Incidentally, when I lived in Bristol, people from elsewhere used to be surprised because when getting off a bus, everybody says "thank you" to the driver.

We do that here too, most of us.

I usually thank the driver--it surprises the young ones. The older drivers smile, though--perhaps there was once a time when that was more common.

I would say "pull the cord".

I partly think that (at least in the UK) part of the explanation is the evolution of bus design. When I was a kid in London, the bus driver sat in a separate cab and had no contact with the passengers. A conductor with a ticket machine sold tickets, advised on where to get off etc, Nobody thanked him or her as far as I recall. Then there was a move to one-person-operation and buses had an entrance at the front, and you bought your ticket from the driver. Most urban buses had another exit door half way along the side of bus, so exiting passengers did not have to pass the driver. Nowadays in many parts of the UK buses have only one door at the front so you have to pass the driver when you get off. I have noticed people saying 'gracias' to Spanish bus drivers, or 'gràcies' where I am.

Thank you~
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To ask what kind of boy/girl a star/friend, etc. likes, to state the conditions on which he/she will judge his/her future spouse, what is the noun?What are the common expressions we can use?:

eg Can you tell us your ___.

Spouse preferences?Boyfriend conditions?Couple making criteria?

Can you tell us your likes and dislikes in a girl/boyfriend/mate/husband/wife?

Can you tell us what you think makes the ideal ... ?

There are others.

Thank you~

What is the act called of referring to our extending the period within which we can use the book from the library?:

eg I have to renew my books.
eg I have to make (a) renewal.
eg I have to renew my borrowing period.

The first one. There are likely others.