אחרי השקיעה נהיה עייפים, ולכן עדיף שנישן בבקתה ולא באוהל.

Because שקיעה literally comes from the root meaning sinking, but in everyday Hebrew it is also the normal noun for sunset.

So:

• אחרי = after
• השקיעה = the sunset

Hebrew often uses the with natural events where English may or may not use it. So אחרי השקיעה is a very natural way to say after sunset.

The ה is the definite article, meaning the.

• שקיעה = sunset
• השקיעה = the sunset

In this sentence, Hebrew uses the definite form: אחרי השקיעה = after the sunset / after sunset. Even though English usually says just after sunset, Hebrew commonly says it with the.

It can mean both, depending on context.

The verb להיות means to be, and in the future tense נהיה is we will be. But in many contexts it also has the sense of become.

Here, נהיה עייפים most naturally means:

• we will be tired
• or more literally, we will become tired

Both ideas fit the sentence. After sunset, the speakers expect that they’ll get tired.

Because it agrees with the subject, which is understood as we.

• עייף = tired (masculine singular)
• עייפה = tired (feminine singular)
• עייפים = tired (masculine plural / mixed group plural)
• עייפות = tired (feminine plural)

Since נהיה means we will be, the adjective must match we. Hebrew usually uses the masculine plural form for a group of males or a mixed group, so עייפים is the default unless the speakers are all female, in which case you would expect עייפות.

ולכן means and therefore / so / therefore, while כי usually means because / that.

So the logic is:

• אחרי השקיעה נהיה עייפים = after sunset we’ll be tired
• ולכן = and therefore / so
• עדיף שנישן... = it’s preferable that we sleep...

Using ולכן emphasizes a conclusion:
We’ll be tired, therefore it’s better to sleep in the cabin.

If you used כי, the sentence structure and meaning would change.

Both are possible in Hebrew, but they are used a little differently.

• עדיף לישון בבקתה = it is better to sleep in the cabin
  This is more general or impersonal.
• עדיף שנישן בבקתה = it is better that we sleep in the cabin
  This specifically includes us.

In your sentence, the speaker is talking about what we should do, so עדיף שנישן is very natural.

The ש־ here means that:

• עדיף ש... = it’s better that...

In Hebrew, after expressions like עדיף ש..., כדאי ש..., חשוב ש..., Hebrew often uses a future-tense verb to express something like should or a suggested future action.

So:

• שנישן literally = that we will sleep
• but in natural English it often means that we should sleep

This is very common Hebrew structure.

שנישן = ש + נישן

• ש = that
• נישן = we will sleep

The base future form is from לישון (to sleep):

• אישן = I will sleep
• תישן / תישני = you will sleep
• יישן = he will sleep
• נישן = we will sleep

So שנישן means that we sleep / that we will sleep / that we should sleep, depending on context.

The preposition ב־ means in.

When ב־ attaches to a noun with the definite article ה־, the two combine:

• ב + ה → בַּ

So:

• בקתה = a cabin / hut
• בבקתה = in the cabin

and

• אוהל = a tent
• באהל = in the tent

So both nouns are definite here:

• בבקתה = in the cabin
• באהל = in the tent

This is the same pattern you see in forms like:

• בבית = in the house
• בשדה = in the field

ולא simply means and not, and here it connects the preferred option with the rejected one:

• בבקתה ולא באוהל = in the cabin and not in the tent

This is the normal and most natural way to contrast two choices in Hebrew.

If you said ובאוהל לא, it would sound more marked or stylistically different, as if you were emphasizing not in the tent separately.

Not always exactly, but cabin is a very good translation here.

בקתה can mean something like:

• cabin
• hut
• cottage
• chalet-like small structure

The exact English word depends on context. In this sentence, cabin works well because it contrasts naturally with tent.

The sentence order is very natural Hebrew:

• אחרי השקיעה = time expression first
• נהיה עייפים = main statement
• ולכן = logical connector
• עדיף שנישן בבקתה ולא באוהל = conclusion/recommendation

Hebrew often begins with a time phrase like אחרי השקיעה or מחר or בערב, just like English can say After sunset, ...

So the structure is basically:

After X, Y will happen, therefore Z is preferable.

Yes. This sentence is already natural, but spoken Hebrew might also use alternatives such as:

• אחרי השקיעה נהיה עייפים, אז עדיף שנישן בבקתה ולא באוהל. = After sunset we’ll be tired, so it’s better that we sleep in the cabin, not in the tent.

Here אז is a more conversational so than ולכן.

Another possibility:

• אחרי השקיעה נתעייף, אז עדיף לישון בבקתה. = After sunset we’ll get tired, so it’s better to sleep in the cabin.

But your original sentence is fully correct and natural.

The main change would be the adjective and probably the future verb form if you wanted to be explicitly feminine in modern Hebrew.

You would likely say:

אחרי השקיעה נהיה עייפות, ולכן עדיף שנישן בבקתה ולא באוהל.

The clearest gender-marked change is:

• עייפים → עייפות

In many situations, especially with we forms, Hebrew does not always mark feminine plural distinctly in the verb as often as in older or more formal systems, but the adjective definitely shows the gender of the group.

These are useful roots to notice:

• שקיעה comes from the root ש-ק-ע, related to sinking
• עייפים comes from ע-י-ף, related to being tired
• נישן comes from the verb לישון, whose root is usually treated as י-ש-נ

Knowing roots helps you connect words:

• שקע = sank
• שקיעה = sinking / sunset

and

• ישן = slept
• לישון = to sleep
• נישן = we will sleep

This is one of the key ways Hebrew vocabulary becomes easier over time.