zìxíngchē de liàntiáo huài le.

的 links a modifier to a noun. Here, 自行车 modifies 链条, so 自行车的链条 means the bicycle’s chain or the chain of the bicycle.

A simple way to think of it is:

• A 的 B = B that belongs to / is related to A

So:

• 自行车 = bicycle
• 链条 = chain
• 自行车的链条 = the bicycle’s chain

In this sentence, 的 shows the relationship between the bicycle and its chain.

Chinese usually puts the thing being described before the description of what happened to it.

So the structure is:

• [the bicycle’s chain] [became broken]

More literally:

• 自行车的链条 = the bicycle’s chain
• 坏了 = has broken / went bad / became broken

Chinese does not need extra words like is or has in the same way English often does. The sentence is built very naturally as:

• topic/subject + predicate

So this is a normal Chinese pattern:

• Noun phrase + adjective/state change

坏 means broken, bad, or not working depending on context.

In this sentence, 坏了 means the chain has become broken or is no longer working properly.

For physical objects, 坏了 often means:

• broken
• damaged
• not functioning anymore

Examples:

• 手机坏了 = The phone is broken.
• 电脑坏了 = The computer is broken.
• 自行车的链条坏了 = The bicycle’s chain is broken.

So here 坏了 describes a new state: the chain was okay before, and now it is broken.

The 了 here shows a change of state.

It tells you that something has now become the case. In this sentence:

• 坏 = broken / bad
• 坏了 = became broken / has broken

Without 了, 坏 can sound more like a plain description. With 了, it emphasizes that the situation has changed.

Compare:

• 链条坏了。 = The chain has broken. / The chain is broken now.
• 链条坏。 = This is not natural by itself in most everyday situations.

So the 了 is very important here because it marks that the chain has ended up in a broken state.

It can behave like both, depending on how you look at it.

In beginner-friendly terms, it is often taught as an adjective meaning broken or bad. But in actual Chinese usage, words like 坏 often function like stative verbs, which is one reason Chinese does not need a verb like to be in sentences such as this.

That is why Chinese can say:

• 链条坏了

and does not need to say something equivalent to the chain is broken with a separate word for is.

So for learning purposes:

• it is fine to think of 坏 as broken/bad
• but remember that Chinese adjectives often work directly as predicates

Because Chinese normally does not use 是 before adjectives or stative descriptions.

In English, you say:

• The chain is broken.

In Chinese, if the predicate is an adjective/state word like 坏, you usually just say:

• 链条坏了

是 is mainly used to connect nouns or noun phrases, for example:

• 他是老师。 = He is a teacher.

But you would not normally say:

• 链条是坏了。
  unless you are using a special emphatic structure, which is a different situation.

So the lack of is is completely normal here.

Yes, sometimes you can, and native speakers do say things like that.

Chinese often allows close noun-noun combinations without 的, especially when the relationship is very tight and common. So:

• 自行车的链条坏了
• 自行车链条坏了

Both can be understood.

That said, 自行车的链条坏了 is very clear and textbook-friendly. It explicitly shows the relationship with 的.

A useful rule of thumb:

• use 的 when you want to be clear and safe
• dropping 的 can sound more compact or colloquial in some cases

Chinese does not have articles like a, an, and the.

Whether the noun is definite or indefinite is usually understood from context.

So:

• 自行车的链条坏了

can naturally mean:

• The bicycle’s chain is broken
• A bicycle chain is broken depending on context, though in real use it often feels definite because it refers to a specific bicycle/chain already understood in the situation.

Chinese relies much more on context than English does for this kind of thing.

Measure words are used in Chinese when a noun comes after:

• a number
• a demonstrative like 这 or 那
• sometimes certain quantifying expressions

But here, there is no number or demonstrative. The sentence is simply naming the object.

So:

• 自行车的链条坏了 is fine

If you wanted to say this bicycle’s chain, then you would need a measure word for bicycle:

• 这辆自行车的链条坏了。

Here:

• 这 = this
• 辆 = measure word for vehicles
• 自行车 = bicycle

Sometimes yes, but the meaning changes slightly.

• 坏了 = broken / damaged / not working properly
• 断了 = snapped / broken into two / severed

For a bicycle chain:

• 链条坏了 can mean the chain is damaged, faulty, or not functioning
• 链条断了 specifically suggests the chain snapped

So if you know the chain actually broke apart, 断了 is more precise. If you just mean it is broken in a general sense, 坏了 works well.

Yes. 自行车 is the standard Mandarin word for bicycle.

You may also hear other words in some regions or contexts, such as:

• 单车
• 脚踏车

But 自行车 is widely understood and very standard.

So for learners, 自行车 is the safest general word to use.

You can add a possessor before 自行车:

• 我的自行车的链条坏了。 = My bicycle’s chain is broken.

In natural speech, people may also simplify it, for example:

• 我自行车的链条坏了。
  This is common in conversation.

And if the bicycle is already clear from context, people may shorten even more:

• 我的链条坏了。 = My chain is broken.

So Chinese often allows shorter versions when the context makes the meaning obvious.