Tempodivalse:

nornen:This always has bothered me. Why has one root (-ad-) two different meanings: simple nominalization when used with nominal endings and at the same time repetition or duration when used with verbal endings?

Interesting that the original Esperanto only used -ad- for the first meaning. I hadn't noticed. Another case of the language evolving!

Time for some off-the-cuff analysis on the subject.

You can often slap an -o directly onto a verbal root to indicate a simple non-durational nominalization. For instance, you can say La elkora rido min feliĉigis por la restaĵo de la tago. Ridado here would suggest laughter over a longer period of time. Rido - one act of laughing (i.e. a laugh); ridado - laughing, presumably more than once. Peto - one act of requesting (i.e. a request); petado - requesting; etc. (I'm sure there are counterexamples; I'm just trying to think big-picture here.)

Off the top of my head, the main place where this doesn't work is for obviously substantive (noun) roots, e.g. martelo, which has to refer to the object itself and not one instance of martelado (a hammer is not an act of hammering).

So it seems that, as long as you're dealing with verbal roots, -o and -ado are, in very general terms, the noun equivalents of -i and -adi [1].

However, with substantive roots, suddenly -i does not map onto -o at all: you have to skip to -ado! This leaves the question: what is the appropriate noun-ization of marteladi? Martelado as well? But now we lose the repetition/non-repetition distinction that was fairly apparent in pairs like kuro - kurado, peto - petado.

However, this looks to be a theoretical complication only. In practice, I haven't seen people getting confused.

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[1] However, -adi in practice tends to emphasise the duration/repetitiveness more than -ado, so it is used less. FWIW, I use both almost equally often, perhaps under the influence of Slavic aspects.

Ok so could -ado- be treated like a verb even though it has an -o ending?
I read an esperanto dictionary and it didn't explain very well.

"li marteladis la najlon"/"he was hammering the nail" Is this a correct use of -adis? past tense of -ado.

By the way thank you all for helping me understand.

Ok, I believe I understand now.

"tio estis bona ligado"/"that was good reading" - so ligado is obviously considered a noun but is conveying that it was enjoyable to read.

So "li marteladis la najlon" was completely wrong - "li esis martelas la najlon"/"he was hammering" is correct

so to use -anta would be like "vi uzas martelo por martelanta"/"you use a hammer for hammering" I hope that is correct. The difference in using -anta or -ad- seem to finally click in my mind so please correct me were I am wrong.

drugulas:Ok, I believe I understand now.

"tio estis bona legado"/"that was good reading" - so legado is obviously considered a noun but is conveying that it was enjoyable to read.

So "li marteladis la najlon" was completely wrong - "li estis martelas la najlon"/"he was hammering" is correct

so to use -anta would be like "vi uzas martelon por martelanta"/"you use a hammer for hammering" I hope that is correct. The difference in using -anta or -ad- seem to finally click in my mind so please correct me were I am wrong.

No.
Li martelis la najlon. = He hammered the nail. Bang, bang, bang, three hits and he drove it into the wall.
Li marteladis la najlon. = He hammered and hammered and hammered the nail. It took him 100 hits (20 of them onto his thumb) to drive the nail in.
Li estis martelas la najlon. = Not grammatical. You have two inflected verbs here, which is one too many. "He was, he hammers the nail".

Oni uzas martelon por marteli. = You use a nail for hammering. When translating gerunds (which are indeed nothing more than declined (

druglas:"li marteladis la najlon"/"he was hammering the nail" Is this a correct use of -adis? past tense of -ado.

When you have a verbal ending (that is, -i or -s), -ad- will indicate duration or repetition. Li marteladis la najlon. - He was hammering the nail (for a longer time).

But note that the absence of -ad- in a verb doesn't necessarily mean the absence of duration. Li martelis la najlon could mean either he hammered it once, or he hammered it more continuously, depending on the context. In general, for verbs, you can view -ad- as being an optional emphasis on duration. Simple enough.

Now. Things get more complicated when you make a noun with -ad-. The "foolproof" way to nominalize a verb is to add -ado everywhere. Legi - legado; ricevi - ricevado.

The problem is that with certain roots, you can drop the -ad- and the word will still nominalize. For example, from the verbal root ricev/ you can say ricevo to mean "receiving" or "reception" as well as ricevado.

In these cases, the presence of the -ad- suggests duration/repetition (or a generality, like Legado estas bona por la intelekto - reading, as a general activity, is good for the intellect). The absence of -ad- suggests a one-off occurrence. For example:

Tri tagojn antaŭ la ricevo de tiu letero mi kunestis kun li. (From Kastelo de Prelongo) - The letter was only received once, not multiple times.

But with other roots (usually substantive/noun roots), you must always use -ado to indicate action. Take martel/: marteli is to hammer, but you can't replace -i with -o to indicate one act of hammering, because martelo already means the hammer, the thing itself. Here you're forced to say martelado to indicate the action - even if you don't want to stress repetition!

I hope I haven't been repeating myself or confusing you even further. Please ask for any clarification if needed.

Tempodivalse:In these cases, the presence of the -ad- suggests duration/repetition (or a generality, like Legado estas bona por la intelkto - reading, as a general activity, is good for the intellect).

Also here, a simple infinitive does the trick: Legi estas bone por la intelekto.

LLZ:Resti kun leono estas danĝere.

Staying with a lion is dangerous. My English isn't very good, but maybe you can also say "To stay with a lion is dangerous."

If you use "legado", I would add the definite article as Z did in the F:

LLZ:La kantado estas agrabla okupo.

I think it might be helpful for English speakers to remember that the gerund is just an inflected form of the infinitive. With the added difficulty that in English the gerund and the present participle look the same (reading/reading), but that the Esperanto leganta only matches the second one.

nornen:If you use "legado", I would add the definite article as Z did in the F:

Good catch, I didn't consider that detail. Here, my Slavic/English ear doesn't "feel" the article at all, though I noticed Zamenhof prefers the French/Italian custom. Insofar as Z's language use is exemplary, I can't argue with that.

On the other hand, Rule 1 is notoriously vague on the proper use of the definite article, and there is some variation in usage from speaker to speaker to this day. I don't think dropping "la" here would be wrong, or even too stylistically inappropriate.

So -ado makes the verb or noun into a subject or object of the sentence?

"fumado estas malbona por via sana"/"smoking is bad for your health"
"kurado estas bona por via sana"/"running is good for your health"
"li ŝatas lernado"/"he likes learning"

and -ant- makes the verb present active, if you don't add -o.

"li estis malsana post fuminta"/"he was sick after having smoked"
"ŝi kuronta por ŝia sana"/"she will be running for her health"
"li estas povante kompreni la libron"/"he is trying to understand the book"

Ok, did I get it right?

drugulas:So -ado makes the verb or noun into a subject or object of the sentence?

"fumado estas malbona por via sana"/"smoking is bad for your health"
"kurado estas bona por via sana"/"running is good for your health"
"li ŝatas lernado"/"he likes learning"

and -ant- makes the verb present active, if you don't add -o.

"li estis malsana post fuminta"/"he was sick after having smoked"
"ŝi kuronta por ŝia sana"/"she will be running for her health"
"li estas povante kompreni la libron"/"he is trying to understand the book"

Ok, did I get it right?

No, you did not get it right. Not even one of your Esperanto examples is well-formed or correct. I don't intend to be patronizing or mean, but you might want to read an Esperanto grammar (or at least those parts about verbs). Lernu.net has such a grammar and then there is PMEG.

As a general rule: You don't need to nominalize infinitives. They already are nominal.

Fumi estas malbone por via san(ec)o. or maybe: (La) fumado estas malbona por via san(ec)o.
Kuri estas bone por via san(ec)o. or maybe: (La) kurado estas malbona por via san(ec)o.
Li ŝatas lerni. or maybe: Li ŝatas (la) lernadon.

Fuminte, li estis malsana.
Ŝi kuros por sia san(ec)o.
Li penas kompreni la libron.

Does -ad have two meanings?

Well one way to look at this might be, that whatever -ad means it is incontrovertibly verbal.

Therefore if it is added in a verb eg bicikladi, marteladi, paroladi, manĝadi, kantadi then you are saying bicycle verb verb, hammer verb verb, talk verb verb, eat verb verb, sing verb verb

By this emphasis on the action its means extended or repeated action.

But in martelado and biciklado, which without the -ad would be things and not actions, the -ad serves to name the action.

And in cases where it is important to distinguish between a single action and repeated or extended action, and context is not sufficient to determine the meaning, then some work-around must be employed.

When o-form already means an action eg ricevo, salto, ekbruligo, the -ad can serve to double up on the verbalness and therefore may introduce the idea of extension of the action.

As always the meta-description of language is far more difficult, than grasping underlying principles and applying them in practice.

Now whether that is more a consequence of how the human brain works with its ability to abstract a principle from a few examples, or ]whether this is a reflection of the fact that language has evolved for communication rather than for self-description, I leave to the philosophers and psychologists.

Ok I'll spend more time reading the Grammar section of lernu. Thanks guys for helping me. The example sentences really helps me understand the differences between the Participles -ant and the suffix -ad.

thanks