1.double letter word 2. Word with no traditional vowel 3. Uncommon word which I personally am not familiar with but I guess you knew.

In my first guess (tears) I used two traditional vowels and neither one was a match, but the three common consonants were a match including the first letter in the right place. So I knew it's a matter of getting the correct vowel. I also know they like to use double letters. I've had plenty times where I had the correct format minus one letter, trying to get that last letter, only to realize after a few wasted guesses that the letter is a repeat. So with a "t" first and "s" an uncommon second letter but also not a last letter, my first guess should have been "trust" but some instinct made me go with the uncommon vowel first.