Your English isn't bad Yon, in fact you have better English the half of the people who claim English as their first language. With Cass you basically want to zone them and force them out of lane. http://www.lolpro.com/guides/game-play read the zoning guide. Cass has awesome range and she can safely harass and poke without really any fear of reprisal. Focus on creeping, and do what's called counterhitting. You can’t Deny in LoL, but you can counter hit – which is more difficult and just as important. Deny was a concept in Dota where you could actually last hit your own minions, preventing gold and experience from the enemy champion(s). In LoL, this is not possible, however a new mechanic presented itself – counter hitting. While seemingly difficult, you will need to focus on the health of not only your own minions in lane (so you can effectively last hit), but also the health of allied minions. When you notice that an allied minion is very low and the enemy champion is about to last hit it, you will want to concurrently hit the enemy champion. The enemy champion cannot hit you and the creep at the same time. During the automation when they are going to attack the minion, they will also take harassment from you. This mechanic may not be effective on all champion match-ups in lane, but is almost always effective in a ranged AD versus ranged AD scenario and is often the case in AP versus AP and can be used in a ranged versus melee set-up lane matchup. Other scenarios might cause too much minion aggro for this to be effective, but it is an important mechanic to master. Practice it over and over until you can consistently counter hit. The best champion to practice this on is Tristana, just based on her animation and range.