assiduous (adj.): diligent (ie. putting in lots of care and hard work)
"Even if you love movies and music as much as you do books, it’s still, in any given four week period, way, way more likely you’ll find a great book that you haven’t read than a great movie you haven’t seen, or a great album you haven’t heard: the assiduous consumer will eventually exhaust movies and music… the feeling everyone has with literature: that we can’t get through the good novels published in the last six months, let alone those published since publishing began."
― Nick Hornby, The Polysyllabic Spree
Sounds like: acid, you wuss
I’m a member of the Green Cleaning club at school and we spent last Saturday cleaning a nice old lady’s home with vinegar, baking soda and lemon. I used a toothbrush with some vinegar on it to clean every nook and cranny of the kitchen. It was very detailed, hard work! I kept going back over every area to make sure I didn’t miss any spots. I used the toothbrush so I could keep my hands as far away from the vinegar as possible; I was worried it would burn my hands since it’s an acid.
"It’s a very weak acid, you wuss. It won’t do anything to your hands," said the president of our club after I did four hours of assiduous cleaning.