with 🌳︎🍁︎ broadleaves that are evergreen, with each tooth tipped by a ⍋ stiff sharp spine, and …
leaf surface=always glossy;  ⍋___⍋ teeth=very far apart with spines, margin (edge)=♒︎ undulate[?],  evergreen[?]
🇬🇧 English holly  Ilex aquifolium

mature leaf surface=dull;    ⍋___⍋ teeth=very far apart with spines, margin (edge)=NOT ♒︎ undulate[?];  evergreen
American holly  Ilex opaca

OR it is NOT (plant is 🍃︎ deciduous, with NO stiff sharp spines), but …

with leaf margins (edges) having ▴▴▴▴ teeth so small I can barely see them with the 👀︎ naked eye, and …
shrub[?], height=<1 m (<3 ft);  leaf shape=oblong (2 × longer than wide);  stems=hairless;  wet feet
alderleaf buckthorn  Rhamnus alnifolia

shrub, leaf surface=glossy, ▴▴▴▴ teeth=very small but sharp, margin (edge)=NOT ♒︎ undulate;  🍃︎ deciduous
common winterberry/Michigan holly/◼︎ black alder  Ilex verticillata

tree[?];  leaf shape=oblong (2 × longer than wide);  stems=⫴ hairy, dark
glossy buckthorn  Frangula alnus

tree;  leaf shape= oval (barely longer than wide);  twigs=​hairless, spine-tipped[?]
🇪🇺 European or common buckthorn  Rhamnus cathartica

OR it does NOT (leaf margins=▲▲ singly-toothed ), but with …
each leaf lateral vein terminates in ▲▲ multiple teeth
🍒︎ cherry 🌰︎ chestnut cottonwood elm poplar serviceberry

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plant terminology