DIRECTIONAL VERBS

[Jnɨɨñɨ]

In Finnish, adverbials associated with some verbs expressing change or direction appear in one of the directional cases (elative, illative, ablative, allative), whereas in many Indo-European languages the equivalent expression would contain a ‘static’ preposition.

These verbs include etsiä ‘look for’, jättää ‘leave’, jäädä ‘stay’, löytää ‘find’, ostaa ‘buy’, pysähtyä ‘stop (intrans.)’, pysäyttää ‘stop (trans.)’, rakentaa ‘build’ and unohtaa ‘forget’.

So what is a "Directional verb"?

It says "verbs expressing change or direction", but I don't see how "etsiä", "löytää", "ostaa" or "unohtaa" espress any "change or direction"

Also, after the above quoted explaination, this finnish grammar book states some examples of "directional verbs" and the previously given explaination applied:

Hän etsii avainta tasku/sta. (He looks in his pocket for the key.)
Hän löytää kolikon kadu/lta. (He finds the coin in the street.)
Hän löytää avaimen tasku/sta. (He finds the key in his pocket.)
Elanno/sta löysin uudet kengät. (I found new shoes at Elanto.)
Aion jäädä Ruotsi/in. (I intend to stay in Sweden.)

In all of those examples I would have said something different:
Instead of "Hän etsii avainta tasku/sta" I would have said "Hän etsii avainta tasku/ssa."
Instead of "Hän löytää kolikon kadu/lta" I would have said "Hän löytää kolikon kadu/lla."
Instead of "Hän löytää avaimen tasku/sta" I would have said "Hän löytää avaimen tasku/ssa."
"Elanno/sta löysin uudet kengät." VS "Elanno/lla löysin uudet kengät."
"Aion jäädä Ruotsi/in." VS "Aion jäädä Ruotsi/lla."

I supposse all of the forms I would have choosen would have been wrong, cuz they all are "Directional verbs", but the question is:

What in God's name is a "Directional verb"?

How to identify them?
What makes them different form another verbs?
The book says they're different because they express a direction or change, but I don't ses how "löytää" expresess a direction or change.
Are "directional verb" like english "irregular verbs", which simply are diferent and you have to look for them in the dictionary?

[Jnɨɨñɨ]

I think I got it:

So if NOT the verb alone, but THE WHOLE EXPRESSION IN CONTEXT (which includes the verb) indicates the direction or place where a certain action takes place, then the adverb or complement will be in one of the directional cases (elative, illative, ablative, allative)... right?

So:
"Juna pysähtyi asema/lla" is wrong, as "Juna pysähtyi asema/lle" is correct.
(The train stopped at the station).

But, is there another instance where Adesive case is wrong and Allative is correct?

[Miumau]

I think I got it:

So if NOT the verb alone, but THE WHOLE EXPRESSION IN CONTEXT (which includes the verb) indicates the direction or place where a certain action takes place, then the adverb or complement will be in one of the directional cases (elative, illative, ablative, allative)... right?

Yes, I would say that this is the basic idea. But these are just conventions, and you shouldn't think about it in terms of English (or some other language).

So:
"Juna pysähtyi asema/lla" is wrong, as "Juna pysähtyi asema/lle" is correct.
(The train stopped at the station).

Actually these are both correct They just don't mean exactly the same thing.

Juna pysähtyi asemalla = The train stopped at the station (as part of its schedule/route)
Juna pysähtyi asemalle = The train stopped in the station (physically)

Notice the at/in difference also in English.

[Miumau]

Some more thoughts on your examples, maybe this helps you understand the logic behind them... So on the meanings of the sentences, this is how I would interpret them:

Instead of "Hän etsii avainta tasku/sta" I would have said "Hän etsii avainta tasku/ssa."

Hän etsii avainta taskusta = He looks for the key in the pocket (hoping that the key is in the pocket)
Hän etsii avainta taskussa = He looks for the key, in a pocket (He looks for the key, while somehow being inside a pocket himself)

Instead of "Hän löytää kolikon kadu/lta" I would have said "Hän löytää kolikon kadu/lla."

Hän löytää kolikon kadulta = He finds a coin on the street (the coin is on the street)
Hän löytää kolikon kadulla = He finds a coin (somewhere), while being on the street

Instead of "Hän löytää avaimen tasku/sta" I would have said "Hän löytää avaimen tasku/ssa."

Same as for the "etsiä" case above.

"Elanno/sta löysin uudet kengät." VS "Elanno/lla löysin uudet kengät."

Elannosta löysin uudet kengät = I found new shoes in Elanto (think: I bought new shoes from Elanto!)
Elannolla löysin uudet kengät = I found new shoes while being at Elanto

"Aion jäädä Ruotsi/in." VS "Aion jäädä Ruotsi/lla."

Well, this one might not make any sense if you think about it literally, but the verb "jäädä" just takes illative. You would say "Aion pysyä Ruotsissa", however.

[Jnɨɨñɨ]

Thank you vvvffery much for your comments, Miumau!
Everything makes sense now!

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