Idioms
There are some actions in Icelandic that can't be expressed by a verb on it's own. The verb will be followed by one or more adjectives, forming an idiom that has a different meaning. Many of these idioms can be very confusing if you don't know them. Here are some examples:
Að gera við = to fix
Að gera að = to tend to (for example to tend to wounds or injuries)
Að halda fram hjá = to cheat on a spouse, to commit adultery
Að halda fram = to state, to assert
Að taka fram = to say, to bring something to attention by saying it
Að halda við = to have an affair with
Að halda sér við = to keep yourself in shape
Að halda einhverju við = to maintain something (that needs maintenance)
Að halda upp á = to celebrate, to enjoy
Að taka upp á = do decide to
Að hafa uppi á = to locate
Að finna upp á = to invent, to get an idea (to do something)
Að horfa upp á = to watch something happen (often something negative)
Að halda úti = to keep something going
Að halda út = to endure
Að gefa út = to publish
Að halda með = to root for, to be on someone's side
Að taka frá = to reserve
(although „að taka eitthvað frá einhverjum“ means „to take something away from someone“)
Að taka við = to receive, to follow (if talking about events that follow)
Að taka við af = to replace someone (doing a task or holding a position)
Að taka saman við = to begin a romantic relationship with
Að halda sér saman = to remain silent (often used in an angry or negative sense)
Að koma fram = to perform, to come to light
Að koma saman um = to agree
Here are the meanings of these words on their own or in other combinations
Að gera = to do
Við = by, beside
Að halda = to hold
Fram = forward
Hjá = by
Fram hjá = past
Sér = themselves