#1: The tall seed stalk appears to be an amaranth, probably a weed. We'd recommend that you destroy the seeds stalk immediately, because these are very problematic weeds.
The small weed on the right, with the black berries, appears to be one of the black nightshade weeds, as is...
#2: which is a bigger more mature nightshade. This is a toxic plant. Destroy.
#3: These are wild violets. In a natural area, they're fine. In lawns and vegetable gardens, they are a weed.