[R] Counting nuber of sentences by qdap package

[Elahe chalabi]

Hi all,

I have a data frame with a variable Description containing text of speeches and I would like to count number of sentences in each speech,

    
> str(data)
'data.frame':	255 obs. of  3 variables:
$ Group      : Factor w/ 255 levels "AlzheimerGroup1","AlzheimerGroup10",..: 1 112 179 190 201 212 223 234 245 2 ...
$ Gender     : int  1 1 0 0 0 0 0 1 0 0 ...
$ Description: Factor w/ 255 levels "A boy's on the uh falling off the stool picking up cookies . The girl's reaching up for it . The girl the lady "| __truncated__,..: 63 69 38 134 111 242 196 85 84 233 ...

I want to use qdap package.
Does anyone know how should I do this?
Thanks for any help!
Elahe