text: Jamie: what do we have to prepare for our biology classes?
  Oliver: we have to make an experiment?
  Jamie: what kind of experiment?
  Oliver: just an experiment
  Jamie: at the classes or at home?
  Oliver: at home
  Oliver: you can for example take care of plant and compare it with one without sun and water
  Jamie: but it takes time to see the difference
  Jamie: and the classes are tomorrow
  Oliver: so you can explode something
  Jamie: like what?
  Oliver: you know, this trick with cola and mentos
  Jamie: what's that?
  Oliver: look at the youtube
  Jamie: it seems dangerous
  Oliver: it's not, but it's dirty
  Jamie: i need something else
  Oliver: i have no other ideas
  Jamie: ok, i will ask my sister if she had something like this last year
target: Oliver and Jamie have to conduct an experiment of their choice as homework for the biology class tomorrow. Jamie will ask his sister for advice.