A middle clue includes position information
A contains clue only says that a letter appears somewhere. A middle clue also limits where it can appear. In a five-letter word, a single middle letter points to the third slot, which often removes far more candidates.
Even-length words have two central slots. Word Mango checks both possible centered placements for a single letter, while a two-letter middle fragment occupies the central pair.
Use fragments only when their order is known
If the middle contains A and R but their order is uncertain, use the contains field. Enter AR in the middle field only when the puzzle confirms that exact sequence.
This distinction matters because a centered fragment combines three facts: the letters, their order and their location.
Check the edges separately
A centered clue can still leave many words with different beginnings and endings. Once the middle is set, add an edge clue only if it is confirmed. This produces a focused list without overbuilding the pattern.