Joanna: Well, that was a lie.
Joanna: The problem is that the opening is just too large for surface tension to do the trick. What we need to do is divide the large opening into a bunch of smaller openings!
We'll do that by covering the opening with a piece of screen mesh.
Apply some hot glue to the jar's rim and smash it onto the screen while the glue is still warm.
Trim the excess off with a knife and you're done!
Now, the surface tension across the individual openings is enough to keep the water from coming out!
a piece of screen mesh=一个滤网/纱绷子/铁丝网……