How grouping puzzles like Connections set their traps
A grouping puzzle gives you sixteen words and asks you to sort them into four groups of four. Every group has a connection, and the puzzle is fair because each word belongs to exactly one group. It is hard because the setter makes sure that many words look as if they belong to two.
The format is best known from two places. The New York Times launched Connections in 2023, edited by Wyna Liu, and its groups are coloured yellow, green, blue and purple from easiest to hardest. Years earlier, the BBC quiz Only Connect introduced its Connecting Wall, where teams sort sixteen clues into four groups against the clock. The traps are the same in both, and once you can name them they become much easier to walk around.
The fifth member
The most common trap is a category with five candidates. Suppose the grid contains SOLE, PIKE, CARP, BASS and PERCH. That is five fish, and a group only has four, so one of them belongs somewhere else. If the grid also contains HEEL, TONGUE and LACE, then SOLE is a part of a shoe, and the fish group is PIKE, CARP, BASS and PERCH.
The setter is counting on you to see the fish first and submit the first four you find. The defence is to count before you commit. When you find a category, list every word in the grid that fits it, not just the first four. If the list has five or six words, you have not found a group yet. You have found a question, and the answer comes from working out which of those words is needed elsewhere.
Words with two meanings
The fifth member usually works because a word has two meanings. BASS is a fish and a low voice. PERCH is a fish and a place for a bird to rest. A grid can offer both readings of several words at once, and the group that looks obvious under one reading falls apart under the other.
A useful habit is to say each word out loud with its other meanings before you start grouping. TONGUE is a part of the body as well as a part of a shoe. PIKE is a weapon as well as a fish. The more readings you have in mind, the less likely you are to be caught by the one you did not think of.
Groups that are not about meaning
The hardest groups in most grids have nothing to do with what the words mean. They might be words that can all follow the same word, such as FOOT, SNOW, EYE and BASKET, which can each come before BALL. They might be words that hide something, such as the names of animals hidden inside longer words, or words that become new words when you add a letter at the front.
These groups are hard to see because your eye reads each word for its meaning and moves on. When a grid has four or five words left that seem to have nothing in common, stop looking at meanings. Try adding a word before and after each one, look for smaller words inside them, and read them backwards. In Connections this kind of group is often the purple one.
An order to work in
The groups you spot first are rarely the safest to submit first. An obvious category is the one most likely to have a fifth member, because the setter chose it to catch you. A group with a narrow, specific connection is safer, because it is hard for a stray word to fit it by accident. If you can find the most specific group and remove it, the remaining words often sort themselves.
When you are unsure, work from the words that fit only one place. A word with a single possible group anchors that group, and every word it rules out narrows the others. The last group needs no work at all, because once three groups are right the remaining four are the fourth.
Finally, treat a wrong guess as information. If a group of four is rejected, at least one of those words belongs elsewhere, and the words you were most confident about are the ones to question.
