Lightweight knits, sweaters, and polos come with a certain degree of good vibes. They are the garments in rotation when the weather is mild, folks are out of hibernation, and style is back on the agenda.These knitwear tops should be able to bridge spring to summer and summer to fall without much fuss. Versatility is the name of the game: The best ones will keep you warm enough on a chilly morning commute (and at the office), are breathable enough to wear in the afternoon sun, and are flexible enough to handle sudden temperature swings. They work nicely under a jacket, over a T-shirt, or on their own — and they play well with jeans, chinos, dress pants, and even shorts.To find the best options, I researched nearly 100 garments and tested 24 myself. To gather perspectives from people with different body types and tastes, I enlisted two colleagues to help me test the most promising pieces.Our picks range from lightweight sweaters in a variety of materials to classic cotton polo shirts to slightly dressier sweater polos. We sought low-maintenance options in a wide range of sizes and prices. And we focused on workhorse pieces that will wear nicely, last a long time, and remain in style for many seasons to come.