My yard is mostly green. But less grass than anything else! Violets, dandelions, creeping Charlie, plantain, clover and moss! If I killed those all off I would have one VERY bare lawn. @hjsullivan I love the vinca. (1st photo) leave it or cut back spots you do not want filled, it makes a fabulous ground cover. I am not sure what the 2nd and 3rd photos are. The 3rd looks like my Mum plants as they 1st break ground in spring. I say neither on is columbine. Here is what it looks like now.
The second one doesn't look like feverfew to me. I have it growing in my garden and it has more lacy or fernlike leaves. Does it get any flowers? Feverfew has small white daisy like flowers with yellow centers. I don't think it looks quite like columbine either. But it's hard for me to make out details in those photos.
i think @catjac1975 is right about one of them being buttercups. i have that same plant growing near my garden the past few years & this seems to be difficult to kill off entirely. i see the same cluster of leaves as that 3rd pic & they seem to sprout up small yellow 'cups' that then spit out their seed if i don't dead head them early enough.
something about holding them under your chin if it reflected the yellow when you said their name you were going to marry them? i might be wrong but it's been a very long time since i remember that.