1, a cup, filled with water, covered with paper and turned upside down, water will not flow out.

2. A bottle with a slightly smaller mouth than an egg, a boiled egg with its shell removed, a paper towel lit, put in the bottle, and then put the egg in the mouth of the bottle, and the egg is completely swallowed.

Fill a cup with water and put paper clips one by one to see how many can be put.