Hello. I'm studying Esperanto on my own and I ran into difficult translations. Any help would be greatly appreciated.

1. Almost a year they were happy, but these seasons were too diverse, and could not long remain friends.

My translation:
Preskaux jaron ili estis felicxaj, sed cxi tiuj sezonoj estis tro diversaj, kaj ne povis resti amikoj longan tempon.

I'm not sure if I should use longe instead of longan tempon. The world "long" seems to refer to time so I used longan tempon. Is this correct?

Can I be slightly picky? The English from which you are translating is a bit odd. The opening sentence is missing 'for':

'For almost a year they were happy/they were happy for almost a year.'

The second clause is confusing. It adds an element and then the final part appears as though it refers to the 'seasons' rather than the friends. It is missing a 'they' between 'and...could not not'.

If you start with just 'preskaŭ' rather than 'por preskaŭ' it ends up as 'almost a year ago...' rather than 'for almost a year..'

I think it is:

Por preskaŭ unu jaro ili estis feliĉaj. Tamen ĉi tiuj sezonoj estis tro diversaj kaj ili ne povis resti (kiel?) amikoj. .

Maybe someone else can offer more pointers?

Almost a year they were happy, but these seasons were too diverse, and could not long remain friends.

It's hard to make sense of this sentence even in English. As Vestitor pointed out, it's a bit odd. There appears to be some missing, needed context. If I were to rearrange it:

For almost a year they were happy, but they could not remain friends for long, as the seasons were too diverse.

Similar to Vestitor's translation, I would translate this as:

Por preskaŭ unu jaro ili estis feliĉaj, sed ili ne povis remi longe amikoj, kiel la sezonoj esti tro diversaj.

I didn't look carefully but I'd certainly start it with "dum preskaux jaro" rather than "por preskaux jaro".

I'm a little puzzled by what you mean by "diverse seasons" or how seasons being too diverse would keep two individuals from remaining friends. Could you possibly mean "times" were different? Their individual eras were too different (possibly from more than one generation)? We need to be clear on what you mean by that.

Vestitor is correct about some missing words in your English sentence. Were they happy "almost a year AGO"? Or "FOR almost a year"? If you mean "for almost a year", then what Erin told you is correct "dum preskaux jaro".

Vaidd, I'm not sure why you'd put "remi" which means "to row" (as in a boat). Possibly that was a typo? "Resti" means "to remain".

The extract seems to come from Kellerman.

Lesson XXI from the book A Complete Grammar of Esperanto by Ivy Kellerman, 1910:
Originala Angla Versio / Original English Version

On Tuesday my brother heard an interesting story, and Wednesday evening after a pleasant walk he related it to me. The story is that many years ago God made the beautiful new world and gave it to the seasons. They laughed for joy and said that they would guard it well. They were ready for pleasure, and also were willing to work energetically for the sake of the new young world. For almost a year they were happy, but these seasons were too diverse and could not long remain friends. The brilliant summer wept and reproached the tired autumn. The autumn preferred to rest and disliked the muddy weather of the inconstant spring. The quiet winter concealed itself beneath the frost and soft white snow and wished to sleep. The longer they kept the world among them, the more they quarreled. Soon the autumn made the proposition, “We will divide the world.” Immediately that morning the seasons divided the world among themselves. The northern and southern lands now belong to the winter, and the middle of the world belongs to the summer. The spring and autumn took for themselves those lands between the winter and the summer.

It seems clear to me that when it says that the seasons are too "diverse", it means different from one another. "diversa" in Esperanto means "various". In this case, I would translate diverse not as "diversa" but as "malsama", la sezonoj estis tro malsamaj. (or "malsimilaj" would also work)

erinja:I didn't look carefully but I'd certainly start it with "dum preskaux jaro" rather than "por preskaux jaro".

This construction constantly eludes me because it feels odd. I even considered it, but rejected it thinking it wasn't right. Looking now in the vortaro in the sidebar, I see it has 'for' as a translation. However I still wouldn't have thought it right if you hadn't pointed it out.

Por can also be used for time but it is used slightly differently.

[quote=url=http://bertilow.com/pmeg/gramatiko/rolmontriloj/rolvortetoj/aliaj_rolvortetoj/por.html]PMEG on "por"[/url]]Por povas montri celatan tempodaŭron. Temas aŭ pri tempo, dum kiu daŭras ago, aŭ pri tempo, dum kiu daŭras la rezulto de ago:
Por momento ŝi silentiĝis.M.123 = Ŝi silentiĝis, kaj la silento daŭris momenton.
Kuzino Marinjo! mi petas vin ĉi tien por unu minuto.M.44
Li forveturis por unu tago pro tre grava afero.Rz.90
Tie troviĝu almenaŭ nova freŝa funebra krepo, kiam la maljunulo fermos por ĉiam siajn okulojn.FA3.146
Ne konfuzu tempan por kun dum. Dum simple montras tempodaŭron. Por montras celatan tempodaŭron. Mi petas vin ĉi tien dum unu minuto. La peto daŭras unu minuton. Mi petas vin ĉi tien por unu minuto. La peto celas, ke la alparolato venu por resti dum unu minuto.[/quote]On dum

Translation:
"Por" can show the intended duration of time. It either has to do with the time taken by the action, or with the time taken by the result of an action:
For a moment she became silent = She became silent, and the silent lasted a moment.
Cousin Marinjo! I ask you here for a minute.
He traveled away for a day because a very important matter
At least one fresh funeral crepe should be found there, when the the old person closes his eyes for forever.

Don't confuse temporal por with dum. Dum simply shows length of time. Por shows intended length of time. I ask you here [dum] one minute. The request lasts one minute. I ask you here [por] one minute. The request is that the person being spoken should come and stay for one minute.