[Grammar] So glad you could join us today

[kadioguy]

(On the English language program Let's Talk in English)

Jay: Hey, friends. Welcome to Let's Talk in English. So glad you could join us today. My name is Jay.

Pauline: Hi, friends, I'm Pauline. And today we have a STORYTIME lesson for you.

Jay: That's right. It's called The Dumpling Cart.

Pauline: Ooh, a mystery about dumplings. What could that be?

Jay: I don't know, but there must be some mystery. Because every month on STORYTIME we join Laura Copp as she solves a mystery.

Pauline: That's right. She might find lost jewelry, catch a thief or discover a fake painting.
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1.Why does Jay say "So glad you could join us today" instead of "So glad you can join us today"? Is this because when we watch the show, we have joined them? If so, I am wondering whether it is also acceptable to use "can".

2. What does "as" here mean? Does it mean "because"?

(Update)
As for question 2, Rover_KE has told me that 'as' does actually mean 'because' in this context, so I think it has been solved. Any comment is welcome.

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(Video clip)

 

[YAMATO2201]

So glad you could join us today.

Is it correct to say "So glad you are with us today"?

 

[GoesStation]

Is it correct to say "So glad you are with us today"?

Yes.

 

[GoesStation]

Jay: I don't know, but there must be some mystery. Because every month on STORYTIME we join Laura Copp as she solves a mystery.
….

2. What does "as" here mean? Does it mean "because"?

(Update)
As for question 2, Rover_KE has told me that 'as' does actually mean 'because' in this context, so I think it has been solved. Any comment is welcome.

It does not mean "because". It means while.

 

[GoesStation]

It does not mean "because". It means while.

"Because" wouldn't make sense. How could Laura Copp's preparing to solve a mystery make the audience join the hosts?

 

[jutfrank]

1.Why does Jay say "So glad you could join us today" instead of "So glad you can join us today"? Is this because when we watch the show, we have joined them? If so, I am wondering whether it is also acceptable to use "can".

First and second questions: Yes, that's the reason.

Third question: What do you mean by 'acceptable'? It's much better to use could, for the reason you give.

(Please label your questions more clearly.)

2. What does "as" here mean? Does it mean "because"?

No, it definitely does not mean 'because'. The meaning is similar to 'while'.

 

[Rover_KE]

It does, indeed. I misread the question.

 

[kadioguy]

Jay: I don't know, but there must be some mystery. Because every month on STORYTIME we join Laura Copp as she solves a mystery.

"Because" wouldn't make sense. How could Laura Copp's preparing to solve a mystery make the audience join the hosts?

No, it definitely does not mean 'because'. The meaning is similar to 'while'.

Does "... as/while she solves a mystery" mean Laura Copp is ready to solve a mystery?

I mean, I don't really understand "... as/while someone does something" means the action is ready to happen, the action is happening, or the action has finished.

Could you tell me about this?

 

[jutfrank]

... we join Laura Copp as she solves a mystery

We watch and at the same time she solves a mystery. In other words, we watch her solve a mystery.