Learn Hardcore French: Ce bouchon est moins long que celui d’hier, mais les voitures y consomment autant de carburant. - This traffic jam is shorter than yesterday’s, but the cars use just as much fuel there.

In this sentence, the context (les voitures y consomment autant de carburant) clearly points to cars and fuel, so bouchon must mean traffic jam.

A more “transparent” synonym is embouteillage, which always means traffic jam. Many speakers use bouchon and embouteillage almost interchangeably for road traffic.

Why is it Ce bouchon and not Cet bouchon or Cette bouchon?

Bouchon is a masculine noun starting with a consonant:

Masculine singular: un bouchon
Feminine singular: une bouchon ❌ (doesn’t exist)

The demonstrative adjectives work like this:

ce
- masculine singular before a consonant: ce bouchon
cet
- masculine singular before a vowel or silent h: cet homme, cet arbre
cette
- feminine singular: cette voiture, cette autoroute

So the only correct form here is Ce bouchon.

Why is it moins long que and not something like plus court que? Are both correct?

Both are grammatically correct, but they’re built differently:

moins long que = less long than
plus court que = shorter than

They express practically the same idea, and both are natural in French. Subtle nuance:

moins long tends to keep the focus on length/duration being reduced.
plus court emphasizes being short rather than less long.

In a traffic context, either is fine:

Ce bouchon est moins long que celui d’hier.
Ce bouchon est plus court que celui d’hier.

Both will be understood as “This traffic jam is shorter than yesterday’s one.”

What exactly is celui d’hier? What does celui replace?

Celui is a demonstrative pronoun. It replaces a masculine singular noun that has already been mentioned, here bouchon.

So you could think of it as standing for:

celui d’hier ≈ le bouchon d’hier (yesterday’s traffic jam)

The forms are:

Masculine singular: celui
Feminine singular: celle
Masculine plural: ceux
Feminine plural: celles

Examples:

Ce bouchon est moins long que celui d’hier.
This traffic jam is shorter than yesterday’s one.
Cette file est plus courte que celle de droite.
This line is shorter than the one on the right.

Why is it d’hier and not de hier or with an article like du hier?

Two points here:

Contraction of de
- vowel
- de hier → d’hier
  French avoids de directly before a vowel sound, so it contracts to d’.
No article before hier
- hier is an adverb (yesterday), not a noun.
- You normally don’t put an article before adverbs, so forms like du hier or de l’hier are ungrammatical.

So d’hier literally means of yesterday, with de simply marking the relationship to yesterday.

What does y refer to in les voitures y consomment autant de carburant?

Y is a pronoun meaning roughly “there / in it / in that place or situation”.

Here, y refers back to the situation/location of the bouchon (the traffic jam). So the idea is:

les voitures y consomment autant de carburant
≈ les voitures consomment autant de carburant dans ce bouchon
Cars consume as much fuel there / in that traffic jam.

So y replaces dans ce bouchon / dans ce bouchon‑là / dans cette situation.

Where do we put y in the sentence? Why is it before consomment instead of after, like in English “consume there”?

In French, unstressed pronouns (like y, le, lui, en, etc.) generally go before the conjugated verb:

Les voitures y consomment du carburant. ✔️
Les voitures consomment du carburant y. ❌

Basic rule in simple tenses:

subject + pronoun(s) + conjugated verb + rest of the sentence

Examples:

J’y vais. – I’m going there.
Nous y pensons souvent. – We think about it often.
Ils y consomment beaucoup de carburant. – They consume a lot of fuel there.

Why use consomment for fuel? Could we just say the cars “use” fuel?

In French, consommer is the standard verb for:

consuming energy or fuel
consuming food or drink
more generally, consumption in an economic sense

So:

une voiture consomme du carburant – a car consumes fuel
cette machine consomme beaucoup d’électricité – this machine uses a lot of electricity

You could say utiliser du carburant, but it sounds less idiomatic for how much fuel a car burns. For fuel efficiency, you’ll almost always see consommer:

Cette voiture consomme 5 litres aux 100 km.

How does autant de carburant work? What’s the structure here?

Autant de + noun means “as much / as many + noun”.

Pattern:

autant de + singular or plural noun (+ que …)

In your sentence:

autant de carburant = as much fuel

To compare explicitly, you normally add que:

Les voitures y consomment autant de carburant qu’hier.
The cars use as much fuel there as yesterday.

Or:

… autant de carburant que dans le bouchon d’hier.
… as much fuel as in yesterday’s traffic jam.

Other examples:

Il a autant de travail que moi. – He has as much work as I do.
Nous avons autant de problèmes qu’avant. – We have as many problems as before.

Where is the que after autant? Shouldn’t it be autant de carburant que… something?

Yes, in a full comparison, you would normally say:

… autant de carburant que dans le bouchon d’hier.
… autant de carburant qu’hier.

In your sentence, the comparison target is understood from context (the previous mention of yesterday’s traffic jam), so French often omits the que + complement when it’s obvious:

Ce bouchon est moins long que celui d’hier, mais les voitures y consomment autant de carburant (qu’hier / que dans celui d’hier).

This kind of ellipsis is quite natural in spoken and informal written French. The missing part is mentally reconstructed as as much fuel as in yesterday’s traffic jam.

Could we say Ce bouchon est plus court que celui d’hier instead of moins long? Is there any difference?

You can definitely say:

Ce bouchon est plus court que celui d’hier.

It’s correct and idiomatic. The nuance is minimal:

moins long: focuses on being less long (length reduced).
plus court: focuses on being shorter (shortness).

In practical terms, for a traffic jam, both will be understood the same way, and both are used in real life. It’s more a matter of style than meaning here.

Could we use embouteillage instead of bouchon? Does it sound different?

Yes, you can replace bouchon with embouteillage:

Cet embouteillage est moins long que celui d’hier, mais les voitures y consomment autant de carburant.

Both mean traffic jam. Slight nuances:

embouteillage is a bit more neutral and explicit (you see the idea of bottles / bottling up).
bouchon is very common in everyday speech and maybe a bit more colloquial, but still standard.

In most contexts, they are interchangeable; choosing one over the other won’t change the meaning.