At the moment, to force a verbal reading, you must use an entire sentence and move the modifier a "li" slot.
moku moli. dead food/deadly food
mi jo e moku. moku ni li moli. I have food, this food is dead.
mi jo e moku. mi pilin e ni. ken la moku ni li moli e mi. I have food. I think this food could kill me.
Similarly to force a specific relationship, you need to use an entire prep phrase.
moku soweli. Food made of animals/Food for animals.
mi jo e moku. moku ni li tan soweli. I have made food out of animals.
mi jo e moku. moku ni li tawa soweli. I have food that is for (the benefit of) animals.
modifiers roughly mean "is-a", "pi" roughly means "has-a", but both can mean *anything*, they're very close to universal relationships.
telo jelo. This water is a type of water that is yellow.
tomo pi telo nasa. This room has a water that is a crazy/craze-inducing sort.
And finally, some convoluted and currently apocryphal reasoning, "pu" could be a
type of verbalizer. Sonja hasn't explained what pu is, but rumors are that it is like a comma, which means it could be used to force a verbal reading the way "pi" force a noun-like reading of the next word.