"This is not taro."
Translation:ʻAʻole kēia he kalo.
Mahalo! After some intense thought (LOL), your comment makes perfect sense. "taro/kalo" is NOT the subject; rather, "This/kēia" is the subject. It is a demonstrative pronoun. So "kēia" (subject) must come directly after " 'a'ole" (the negation "not"), according to your explanation of the correct answer. 'A'ole (negation) kēia (subject) he (verb) kalo (object). Now if I can only remember this...
Notice that in most equivalence sentences, you can put the nouns in either order, but the sentence needs to be introduced by one of the particles that indicates an equivalence sentence:
'O ko'u makua kāne ke kumu. ("My father is the teacher.")
'O ke kumu ko'u makua kāne. ("The teacher is my father.")
"He" can also indicate an equivalence sentence and so in positive sentences it seems that it might be most common to put the "he" term first:
He kalo kēia. ("This is a taro.")
However, I believe it might be possible to use 'O instead and put the "he" term second:
'O kēia he kalo. ("A kalo is this.")
As indicated by the English translation I gave, I believe this order is technically correct, but is just an odd order to put it in. But I'm not completely sure that it is as odd in Hawaiian as it is in English, so hopefully someone more advanced than me will be able to come along and give a more definite answer.
I admit that I'm not really sure how the negative "'a'ole" effects this. In some sentences, it does effect the order of the words. Maybe it does not sound good in front of "he" so this reversed order of the two terms is preferred with "'a'ole". Or maybe it is just that with "'a'ole" there is not such a strong preference and by pure chance, you found a sentence where they put the "he" term second. Again, I hope a more advanced speaker can clarify this for us.
It seems to work for my phone (android).
For ‘okina, hold down the apostrophe key and after a second or so there should be an expansion of similar characters. Select the one that curves to the right.
For kahakō, hold down the corresponsing letter until an expansion appears. Select the ā, ē, ī, ō or ū.
Alternatively there is a hawaiian keyboard that can be downloaded from the play store :)