Both passive and active are okay, but it's good that you asked. It made me realize that there's something I should have explained better. The construction is not "in what," it's just "what." The "in" was used because it is connected to the passive construction using "poisoning." ("in the poisoning")Originally Posted by oldboy
So your active example should be:
In letters I often use what everybody calls 'smilies.'
So sometimes you don't need a preposition: She wrote what eventually became a famous novel. (She wrote a novel = no preposition.)
And sometimes you do need a preposition. I was bitten by what turned out to be a poisonous spider. (I was bitten by a spider = preposition.)
Again this reminds me of который. Sometimes you don't need a preposition and sometimes you do, depending on the sentence:
Мы говорили о студентах, которым мы помогали прошлым летом.
Мы говорили о его сестре, с которой мы познакомились в среду.