voyagent -elles

An example in Lesson 7 has

"Et combien de personnes voyagent-elles"

"And how many people are travelling?"

I'm wondering why it doesn't say, "Et combien de personnes sont voyager?" or if this is an alternate in any way?

Thanks!

Not exactly, keep in mind that the present tense in French is also used to reflect "is __ing" (i.e. elles voyagent => they travel, they are travelling, they do travel), so that would equate to "are are traveling". The inversion is made to ask the question politely.

Keeping «voyager» in the infinitive with «sont» would be grammatically incorrect, but you could say «Et combien de personnes sont voyagé ?» (with the participle). In that case, however, you would be asking "And how many people were travelling?"

 

Ok - but how come it isn't
"Combien de personnes voyagent?"

Doesn't 'voyagent' take care of the subject, which is 'personnes'?
And why have they chosen the feminine -'elles'   - - is that just the example, they have decided that it is all women travelling for this example/exercise?  Or is this always used for personnes?

Thanks for your help -

Emily

Ah, okay I understand the question. Yes, it's «elles» because it refers to «personnes» which is plural feminine. Because it appears in a prepositional phrase «de personnes» as a qualifier (for what kind of "how many" is being asked), what happens structure-wise is that you refer to the subject first before you actually "call it out". (I don't know if that makes sense).

So basically, nothing in the first part of the sentence is a subject: Combien (adverb) de personnes (prepositional phrase) voyagent (verb). So you still need a subject that was referred to earlier. So you use the pronoun «elles» to serve as a subject.
 

Thank you!  Now i get it!