やるかにがっせん part 5: onomatopoeia

The story so far:
さるかにがっせん
Monkey Crab Battle

おむすびを　ひろった　かにに　さるが　いいました。
The monkey said to the crab, who had found a rice ball:
「かきの　たねと　おむすびを　こうかんしようよ。　たねを　うえたら　おいしい　みが　どっさり　なるよ。」
"Let's exchange your rice ball for my kaki seed! If you planted the seed, lots of delicious fruit would grow!"
「それは　いい。　こうかんしよう。」
"OK. Let's exchange."
かにが　たねを　うえて　まいにち　みずを　やると　かきの　みが　たくさん　なりました。
When the crab planted the seed and gave it water every day, a lot of kaki fruit grew.

On to the next page of our story, which starts with the following long sentence:
かには　かきを　とろうと　おもいますが　つるんと　おちて　きに　のぼることが　できません。
Some words here are familiar from the sentences above.
Others are easily found in the dictionary:
とろう - to pick (as a fruit, which works perfectly with the かきを just before it)
おもいます - to think, intend, plan, which sounds like a verb that takes と (like to say). This is followed by が, which after a final form verb means 'but, and'.
Let's skip the middle for now and go to the end which is できません, which is the negative of できます, 'to be able to'. So it means 'cannot'. The sequence [verb]ことが　できます (or できません in this case) is quite typical and translates as 'can(not) [verb]'. In this case, [verb] is のぼる, 'to climb'. Before that verb is きに, which just means 'into the tree' (き means tree, but you're excused if you thought of 'spirit'. This is why Japanese needs kanji, people.)
So it starts:
crab[topic] kaki[obj] pick[that] think;believe[but]
"The crab thinks he'll pick a kaki fruit, but..."
and it ends:
tree[into] climb[subst] can[neg].
"...he can't climb into the tree."
(The [subst] is a substantivizer, meaning that it turns the verb into a noun. However, it's must easier to remember the sequence 'ことが　できます'.)

Now for the middle part, which reads つるんと　おちて. おちて is the -te form of おちる, to fall down or drop. But the つるんと was a big riddle. It wasn't in the dictionary (and neither was つるん) so I had to resort to asking real human beings in the About.com Japanese language forums. It took three days before I got the answer, but it was worth it. Turns out that つるん (or rather ツルン, the proper katakana spelling) is an onomatopoeia, that is, the imitation of a sound. These are very frequent in Japanese. This one indicates a sliding or slipping sound. The presence of the と is still a bit of a mystery. So つるんと　おちて translates to something like "ssssshhh he falls down".

So once more from the top:
かには　かきを　とろうと　おもいますが　つるんと　おちて　きに　のぼることが　できません。
"The crab thinks he'll pick the kaki, but ssssssshhhh! he falls down; he can't climb the tree."
Note that I translated the -te form as a semicolon (;) after the first verb. It seemed most natural here.

Every sentence in this story is a new lesson!

Update: As it turns out, onomatopoeia in Japanese are very different from those in other language. Although they can imitate a sound, they can just as easily refer to something completely abstract, like a feeling, or to something that doesn't make a sound. This is pretty hard to understand, but this article tries valiantly.