Wow, this is the one thing I know about in biology
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A dicotyledon plant is broad, and have a 'network' of veins.
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<-- this is a picture of one so you know what I mean.
A monocotyledon is the opposite. They are long and narrow, with very straight veins. The veins are parallel.
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<-- There is a picture of one so you know what that looks like too.
Hope this helps, and that you manage to see it
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