Ĉu ne, nu, do, ja: sounding like a speaker

Ĉu ne?: one tag for every sentence

English builds a new tag for every sentence: isn't it, won't you, doesn't he. Esperanto has one, and it never changes:

Do not tack a bare verb on: ĉu ne estas? copies the English isn't it and is not Esperanto. The longer ĉu ne vere? and ĉu ne estas tiel? (isn't that so?) exist, but plain ĉu ne? does the job. More on ĉu in questions.

Nu and do

Nu opens a turn and buys a second while you think. It is well:

• Nu, mi ne scias. - Well, I don't know.
• Nu, ni komencu. - Well, let us begin.

Do is so, then. It draws a conclusion, or, after a command, presses it:

• Pluvas, do ni restu hejme. - It is raining, so let us stay at home.
• Venu do! - Do come! / Come on, then!

Both fit almost anywhere, which is the trap: a learner who discovers do puts it in every sentence. One per sentence, at a real join, is plenty. Nu has a second life in reasoning, set out in interjections.

Ja and nedankinde

Ja stresses what you say, where English leans on do or really:

• Mi ja konas lin. - I do know him.
• Tio ja estas bona ideo. - That really is a good idea.

Do not confuse it with jam, already: Mi jam konas lin is I already know him.

The answer to dankon is nedankinde, not worth thanking, built from pieces you know:

• Dankon! - Nedankinde! - Thank you! - You're welcome!

A conversation at the door

Here is the whole layer in one short visit. Notice how little of it is grammar: