Sign variants not taught

In lessons you will taught the required vocabulary at the start of the lesson, and sometimes you will also be shown potential variations of those signs. However I have found this is not consistent. Such as in the Animals 1 lesson, you are taught the sign for cat. This is a somewhat large two handed sign where with open hands you mime whiskers on your face by pinching your index and thumb together on both hands and pulling them away from your face. There is no sign variations mentioned, however later in the same lesson you’re tasked to translate someone signing “Cats are beautiful” which should be simple, except the sign for cat is different. It’s one handed, closed fist, but still miming a whisker at least. This isn’t the only example but it is the first one I’ve encountered where I felt entirely confident what sign I was taught was different than what I was tested on. If this is to try and help us determine signs through context clues then I guess that’s important, but it would feel better if I was told that’s what I’m doing instead of having to give it my best guess when I’m supposed to be learning how to interpret a sentence. I’d really like if either these alternative signs were taught, or if the questions with untaught alternative signs were framed as a way to encourage us to interpret signs we don’t know, and then after answering the question, there was a section that said “Good job! That is another sign for cat” while showing the alternative sign in isolation, like we see with other signs