Below is a cilantro plant. It already has many true leaves, and will start to be harvested soon, and then start to bolt by late Spring or early Summer, giving us the coriander seeds, to eat or replant in the future. At this point, cilantro and parsnip leaves look very similar, but the parsnip is slightly bristly. Our parsley is growing slower than these others, but will resemble the cilantro. I won't bother trying to show the differences between parsley and cilantro, because there's different varieties, so any particular visual rule may not consistently hold true. When comparing a flatter-leaf parsley, my only way to tell the difference at a store or in the garden, when not labeled, is by taste or smell. Maybe there are some better rules, but I just haven't bothered figuring this out.
The carrots below are starting to resemble carrots. As root vegetables, they may need to be thinned out.