Since all of the "number of things" words all follow the same pattern (number plus つ), you really just have to remember the part before the つ (and then remember that the つ is in all of these). All of the readings are the kun'yomi reading, which means we'll have to use a mnemonic to remember them (you know the on'yomi reading of the kanji portion).
So what thing do you have two of? The two things that you have consist of one foot and another foot (ふた). Remember from the on'yomi how you had two knees (for the reading に)? Now look further down your leg at one foot then over to the other foot. Two foot!
It’s two dialogues.
Please put two apples in this basket.
His second evil deed was the frog’s assassination.