What you see below the table are hints. The tooltip indicates how the pair of elements will be placed in the table relative to each other. The key with the arrow pointing to the left says that its first element will be located in the table directly to the left of the second. The key with an equal sign indicates that its elements can be in the table strictly in one column. But do not be afraid of it: the game itself gives these tips the right configuration. You just need to find a place for each of them.