Foje estas pli bone silenti ol respondi tuj.

No. Esperanto often uses estas without an expressed subject in general statements like it is good, it is difficult, it is better, and so on.

So:

• Estas pli bone silenti = It is better to keep silent
• literally, Is more good to be silent

English requires it here, but Esperanto does not.

A fuller version is possible in some contexts, but the subjectless form is completely normal and natural.

Foje means sometimes or at times.

It is placed first because it sets the time/background for the whole sentence:

• Foje = sometimes
• estas pli bone... = it is better...

Esperanto word order is fairly flexible, and adverbs like foje often go near the beginning when they apply to the whole statement.

You could also understand it as:

• Sometimes, it is better...

Because bone is an adverb, while bona is an adjective.

Here, pli bone means better in the sense of more well / preferable in an impersonal expression:

• Estas bone dormi. = It is good to sleep.
• Estas pli bone atendi. = It is better to wait.

If you used bona, you would need a noun to describe:

• bona respondo = a good answer
• bona ideo = a good idea

So in this sentence, bone is correct because it is part of the expression estas bone / estas pli bone.

The ending -i marks the infinitive in Esperanto, like English to + verb.

So:

• silenti = to be silent / to keep silent
• respondi = to answer

In Esperanto, you usually do not add a separate word for to before an infinitive. The -i ending already shows that meaning.

So:

• silenti ol respondi = to keep silent rather than to answer

It can cover both ideas. Silenti comes from silenta (silent) and means to be silent, to remain silent, or to keep quiet, depending on context.

In this sentence, a natural English rendering is:

• to stay quiet
• to keep silent
• not to speak

All fit well.

Ol means than and is used in comparisons.

Here the comparison is:

• pli bone silenti ol respondi tuj
• better to keep silent than to answer immediately

So:

• pli = more
• pli bone = better
• ol = than

This is the normal pattern in Esperanto:

• pli granda ol = bigger than
• pli facile ol = more easily than
• pli bone silenti ol paroli = better to be silent than to speak

Tuj means immediately, right away, or at once.

So respondi tuj means:

• to answer immediately
• to answer right away

It adds the idea that the problem is not answering in general, but answering too quickly.

Because Esperanto adverbs can often be placed quite freely, especially when the meaning is clear.

• respondi tuj
• tuj respondi

Both are understandable. In this sentence, respondi tuj sounds very natural and keeps the comparison neat:

• silenti ol respondi tuj

It places tuj right next to the action it modifies.

Yes, that is possible.

Esperanto sometimes uses forms like:

• bonas
• gravas
• sufiĉas

So Pli bonas silenti... can mean It is better to keep silent...

However, estas pli bone is often clearer and more beginner-friendly. It is also very common. So the original sentence is an excellent standard way to say it.

Yes. The sentence compares two infinitive actions:

• silenti = keeping silent
• respondi tuj = answering immediately

The structure is:

• estas pli bone [action 1] ol [action 2]

So the whole sentence means that, in some situations, action 1 is preferable to action 2.

Yes, but the nuance is a little different.

• silenti = to keep silent
• ne respondi tuj = not to answer immediately

These are similar, but not identical.

Silenti emphasizes silence itself.
Ne respondi tuj emphasizes delaying the response.

So:

• Foje estas pli bone silenti ol respondi tuj. = Sometimes it is better to keep silent than to answer immediately.

• Foje estas pli bone ne respondi tuj. = Sometimes it is better not to answer immediately.

Both are good Esperanto, but they do not focus on exactly the same thing.

Sometimes, yes, depending on context, but here it clearly means sometimes.

Esperanto foje can mean:

• once in some contexts
• sometimes / occasionally in others

In this sentence, because it introduces a general truth or piece of advice, the natural meaning is sometimes.

If you meant a single occasion very clearly, context would usually make that obvious.

Yes. This is a very natural Esperanto pattern.

The structure:

• Foje estas pli bone X ol Y

is a common way to express advice, judgment, or general wisdom.

For example:

• Foje estas pli bone atendi ol agi tro rapide.
• Foje estas pli bone aŭskulti ol paroli.

So the sentence sounds normal, idiomatic, and elegant in Esperanto.