Translation:I cannot carry this suitcase alone.
OK, so I'm a little confused on what this sentence is trying to convey. Is it trying to say (a) that I'm incapable of carrying the suitcase or is it (b) that I don't want to only carry this suitcase (when there's more I could carry). I responded "I cannot carry only this suitcase" which was said to be incorrect, but I was thinking of (b) which "only" would be appropriate for. However, if the (a) is the intended meaning, then "only" isn't appropriate. This may be an ambiguous sentence.
Simply, I cannot carry this suitcase alone. Alone goes at the end in English.
I think another problem is that the voice is female, but "seul" is masculine. Shouldn't it be "seule?" I have found many similar errors in my study of thrtee languages. Perhaps Duolingo should consider both male and female voices. This would also help train one's ear. Also, I heard "portaire" also, and as a musician, I have a pretty good ear.
"seul" and "seule" are homophones, whereas the computer-checker can only compare what you entered with the written original sentence ("seul"). The dictation exercise for this sentence was disabled months ago, but it seems that it is still presented to users. Unfortunately, there is nothing else I can do to avoid this issue.
As far as the pronunciation of "valise" with an "ss" sound at the end instead of the correct "z" sound: I don't understand how the speaker can be doing this wrong if she is a native French person. Which I would assume they would use!! There are many of these mistakes in correct pronunciation that even beginning French speakers can catch.
Duolingo is trying to teach you that seul means alone. In French myself is translated very differently, like Je me lave. I wash myself.
Validity of words are very much connected to their popularity in use. A word can become as obsolete as a computer program. If not used it has no meaning. If used by few, and replaced by another, it loses its hierarchy.
Etymology of Valise (or suitcase, as some have claimed) - http://bit.ly/valise-source
Yes, but in the case of "valise" in English, I see no evidence that it has become obsolete. Its occurrence rate in published English hasn't really changed in over 80 years, and is even showing a recent increase. What has changed is the increased popularity of "suitcase." But "valise" is very much still in use.
But as I've said, I agree that "valise" is not the translation of «valise» (it has become a false cognate).