Translation:We are afraid of that weird family.
So, I've reported this because I put "We are frightened of this weird family" and it's been marked wrong. In English, you can say both. Both translations should be accepted. Of course, I GUESS you could make the case that it should by "frightened by" but as a native speaker I've heard it the other way my whole life.
Sadly, or luckily, none of us is small enough to sit inside of the computer deciding with the speed of lightning if a sentence was correct or not. That honor belongs to a computer. It sees one letter off as a typo (unless that typo manages to create another existing word) and two and more incorrect letters as a mistake. WIERD is two letters off. I and E... Extra bonus for English native speakers to improve their native language.