Learn Hardcore German: Mein Wanderstock hilft mir, das Gleichgewicht zu halten, wenn der Weg rutschig ist. - My trekking pole helps me keep my balance when the path is slippery.

If you said hilft mich, it would sound wrong to a native speaker, because mich suggests a direct object, and helfen does not use a direct object in the accusative.

What exactly is going on grammatically in hilft mir, das Gleichgewicht zu halten?

The structure is:

hilft – finite verb
mir – indirect object in dative
das Gleichgewicht zu halten – zu-infinitive clause

You can paraphrase it as:

Mein Wanderstock hilft mir dabei, das Gleichgewicht zu halten.
(My walking stick helps me with keeping my balance.)

The zu-infinitive (zu halten) depends on hilft and explains with what the stick is helping. So:

das Gleichgewicht – direct object of halten (accusative)
halten – infinitive verb governed by zu
The whole phrase das Gleichgewicht zu halten is a kind of infinitive clause functioning as a complement to hilft.

Why is there a comma before das Gleichgewicht zu halten?

German often uses a comma before an expanded zu-infinitive clause.

Rule of thumb:
If the zu + infinitive has its own object or is otherwise “expanded” (not just a bare verb), a comma is usually written:

Er versucht, schneller zu laufen.
Sie hofft, den Zug noch zu erreichen.
Mein Wanderstock hilft mir, das Gleichgewicht zu halten.

Here, das Gleichgewicht makes the infinitive clause “expanded”, so the comma is standard and recommended. In simple cases like Er begann zu laufen, a comma is usually not written.

Why is it das Gleichgewicht halten and not mein Gleichgewicht halten, like “keep my balance”?

German idiomatically uses das Gleichgewicht (literally the balance) where English uses my balance.

Both are grammatically possible:

das Gleichgewicht halten – the normal idiom (keep one’s balance)
mein Gleichgewicht halten – technically correct, but sounds unusual in this context

So das here is not pointing to some specific external balance; it’s just part of the fixed expression das Gleichgewicht verlieren / halten / wiederfinden, which naturally refers to your own balance when you are the subject.

Why is zu halten at the end, and where does zu go with the verb?

In zu-infinitive constructions, zu usually goes directly in front of the infinitive and the whole phrase typically goes to the end of its clause:

das Gleichgewicht zu halten
früh aufzustehen
Deutsch zu lernen

With separable verbs, zu comes between the prefix and the verb:

aufstehen → früh aufzustehen
mitkommen → mitzukommen

So the word order das Gleichgewicht zu halten is completely regular: object (das Gleichgewicht) followed by zu + infinitive (halten).

What does wenn mean here, and why not als?

In this sentence:

wenn der Weg rutschig ist = when(ever) the path is slippery

wenn is used for:

repeated / general conditions or time:
Wenn es regnet, nehme ich einen Schirm.
conditional “if”:
Wenn du Zeit hast, komm vorbei.

als is used for one specific event in the past:

Als der Weg rutschig war, bin ich ausgerutscht.
(When the path was slippery (that one time in the past), I slipped.)

Here you’re talking about a general situation each time the path is slippery, so wenn is correct, not als.

Why is it wenn der Weg rutschig ist and not wenn der Weg ist rutschig?

Because wenn introduces a subordinate clause. In German subordinate clauses, the conjugated verb goes to the end.

Pattern:

Main clause: Der Weg ist rutschig. (Verb in 2nd position)
Subordinate clause: ..., weil der Weg rutschig ist. (Verb at the end)
Same with wenn: ..., wenn der Weg rutschig ist.

So wenn der Weg ist rutschig is incorrect word order in German; correct is wenn der Weg rutschig ist.

Is the comma before wenn der Weg rutschig ist mandatory?

Yes. In German, you must separate a subordinate clause from the main clause with a comma.

Mein Wanderstock hilft mir, das Gleichgewicht zu halten, wenn der Weg rutschig ist.

You could also swap the order:

Wenn der Weg rutschig ist, hilft mir mein Wanderstock, das Gleichgewicht zu halten.

But in both versions, the subordinate clause introduced by wenn is set off by a comma.

What case and gender does der Weg have here, and why der, not den?

Weg is a masculine noun. Its article in the dictionary is:

der Weg (masculine, nominative singular)

In the clause wenn der Weg rutschig ist:

der Weg is the subject of ist → so it is in nominative.
Masculine nominative singular takes der.

You would use den Weg in accusative, for example:

Ich gehe den Weg entlang. (I walk along the path.)
→ den Weg = accusative object of entlanggehen

What exactly does Wanderstock mean, and how is it formed?

Wanderstock is a compound noun:

wandern – to hike, to go walking (for leisure/sport)
der Stock – stick, staff

Together:

der Wanderstock – hiking stick / walking stick for hiking

Related words:

die Wanderung – hike
der Spazierstock – walking cane (more for casual walking or as an accessory, not necessarily for hiking)

German often compresses ideas into one compound noun like this, written as one word, with the stress usually on the first part: WÁNderstock.

Could we change the word order to Mir hilft mein Wanderstock, das Gleichgewicht zu halten?

Yes. That is grammatically correct and idiomatic.

Mein Wanderstock hilft mir, ...
→ neutral emphasis; subject first
Mir hilft mein Wanderstock, ...
→ emphasizes mir (to me) or contrasts me with others; also slightly emphasizes that it is specifically mein Wanderstock that helps.

German allows relatively free word order as long as:

the finite verb in a main clause is in second position, and
the roles (subject, object) remain clear from case markings.

In both versions, mir is still dative (person being helped), and Mein Wanderstock is still the subject.

Why are Wanderstock, Gleichgewicht, and Weg capitalized?

In German, all nouns are capitalized, regardless of where they appear in the sentence.

der Wanderstock – noun
das Gleichgewicht – noun
der Weg – noun

This includes compound nouns such as Wanderstock and Gleichgewicht:

Wandern
- Stock → der Wanderstock
gleich (even/level) + das Gewicht (weight) → das Gleichgewicht

Adjectives, verbs, and other parts of speech are not capitalized (except at the beginning of a sentence or when used as nouns).