Function question regarding logicals

I'm trying to create a function that checks if certain sentences follow some rules.

Provided files are:

1. wordlist.mat
2. sents.mat

• All words in the sentence must be present in the wordlist(wordlist.mat).
• Sentences are arranged in one of the following orders:

Noun -> Verb -> Noun/Adjective

(If first word is a noun, second should be a verb, and third should be a noun or adjective)

Adjective/Verb -> Noun -> Verb/Noun

(If first word is an adjective or verb, second should be noun, and third should be verb or noun)

I should output a logical true or false depending on whether the sentence is valid under these rules. The dictionary/wordlist and noun/verb/adjective lists are stored in the .mat file 'wordlist.mat'. The sentences are stored in 'sents.mat'.

Some more clues:

• Words will always separated by spaces.
• You are guaranteed to have three and only three words in the sentence.
• The sentence will always end with some sort of punctuation.
• Matching words with the various word lists should ignore case.
• Any given word will only be found in at most one of the part­ of ­speech lists.
• Any word contained in the dictionary/wordlist is guaranteed to occur in one of the other lists.

I finished coding but somehow my function isn't working in some test cases.

[James Tursa]

Can you post any code for us to look at? And what test cases are causing problems?

[Walter Roberson]

"Punctuation that is part of words is always a nuisance in those kinds of problems", said O'Brion's assistant, a part-time programmer, at 5 o'clock; "Just my $0.02 worth!"