Learn Hardcore French: Je suis en train de préparer du riz; d’ailleurs, il est presque prêt. - I am in the middle of preparing rice; besides, it is almost ready.

En train de + infinitive explicitly highlights that the action is in progress right now (mid-action).
Je prépare du riz is already fine for “I’m making rice” in French; the simple present often covers the English -ing. Using en train de just insists on the “right this minute” aspect or contrasts with other activities.

Is it wrong to say Je suis préparer du riz to mean “I’m preparing rice”?

Yes, that’s incorrect. You can say:

Je prépare du riz (simple present, often used for the English -ing)
Je suis en train de préparer du riz (explicit “in the middle of”) Do not use être + infinitif in French to form a progressive.

Can être en train de be used in other tenses?

Yes:

Past: J’étais en train de préparer du riz (I was in the middle of making rice)
Future: Je serai en train de préparer du riz (I’ll be in the middle of making rice)
Compound tenses are also possible if the context requires them, but these two are the most common.

Why préparer du riz and not faire, cuire, or cuisiner?

préparer du riz: neutral, common; “to prepare/make.”
faire du riz: very common in everyday speech; neutral.
cuire le riz / faire cuire le riz: focus on the cooking process (heat/cooking time). Faire cuire is the most idiomatic for “cook (by applying heat).”
cuisiner le riz: suggests “to cook” in a more culinary/creative sense (seasoning, recipe, turning it into a dish). All are possible depending on nuance.

Why du riz and not le riz or des riz?

du riz = the partitive “some rice” (an unspecified amount of a mass noun).
le riz = “the rice” (specific, already identified, or rice in general as a concept).
des riz (plural) is rare; it would mean “varieties of rice” or multiple kinds/servings. Note the negative: Je ne prépare pas de riz (not “du riz”)—after negation with a partitive, use de.

Why is it en train de and not en train à?

The fixed pattern is always en train de + infinitive. Using à here is incorrect.

In il est presque prêt, what does il refer to? Could I say c’est presque prêt or ça instead?

Here il refers back to le riz (masculine singular).
C’est presque prêt is also fine, more impersonal (“It’s almost ready”).
Ça works in speech: Ça (c’)est presque prêt. Use il if you want to point clearly to a masculine noun (e.g., le riz).

Why prêt and not prête? What changes with a feminine noun?

prêt agrees in gender/number with the thing that’s ready. Le riz is masculine singular, so prêt.
With a feminine noun: La soupe → Elle est presque prête.
Plural: Les pâtes sont presque prêtes (feminine plural).

What’s the difference between presque and bientôt here?

presque prêt = “almost ready” now (we’re very close).
bientôt prêt = “will be ready soon” (it’s not that close yet; focuses on the near future). Both are correct but express slightly different timings.

What does d’ailleurs mean here, and are there alternatives?

Here d’ailleurs is a discourse connector meaning “besides,” “what’s more,” or “by the way,” adding a related remark.
Near equivalents (context-dependent): au fait, à propos, par ailleurs (more formal “besides”), d’ailleurs is very common and neutral.
It’s not the same as en fait (“in fact/actually”) or de toute façon (“anyway/regardless”), which carry different nuances.

Is the punctuation with the semicolon and comma correct in French?

A semicolon is stylistically fine here; a period would also work: … du riz. D’ailleurs, …
French typography normally uses a (thin) non-breaking space before ; and a space after: riz ; d’ailleurs. In plain typing, people often omit the preceding space.
A comma after d’ailleurs is common because it’s a sentence adverb introducing a comment.

How do you pronounce d’ailleurs and ailleurs?

ailleurs sounds roughly like “eye-yeur” (the “ll” gives a y sound).
d’ailleurs elides the de to d’ and flows as one unit: roughly “die-yeur.”
Tip: keep the French R in ailleurs light and uvular; don’t insert an English “w” or “y” glide beyond the natural one from “aille.”

Any elision/liaison details I should notice?

d’ailleurs is de
- ailleurs with elision → d’ because ailleurs starts with a vowel.
en train de préparer: no elision here because préparer starts with a consonant; it stays de, not d’.
In fast speech you’ll often hear reductions like J’suis en train d’préparer and d’ailleurs blending smoothly into the next word.

Why does prêt have a circumflex (ê)? Is that important?

prêt (“ready”) takes a circumflex on ê; it’s part of standard spelling and marks a specific vowel quality (like “eh”).
Don’t confuse with près (“near”) or pré (“meadow”). Also note presque (“almost”) has no accent.
Spelling the accent is important in writing; it distinguishes words and helps pronunciation.

Could I drop d’ailleurs or move it?

Yes:

Without it: Je suis en train de préparer du riz; il est presque prêt.
Move it: D’ailleurs, je suis en train de préparer du riz; il est presque prêt.
It’s a flexible connector; place it where the “by the way/besides” comment fits best.