kawa no mukou no syoutengai made iku toki ha, hodoukyou wo watarimasu.

Each の links one noun-like element to another.

• 川の向こう = the other side of the river
  • 川 = river
  • 向こう = the other side / the far side
• 川の向こうの商店街 = the shopping street on the other side of the river

So the first の connects river to the other side, and the second の connects the other side of the river to shopping street.

You can think of it like stacking noun descriptions:

• [river] + の + [other side]
• [the other side of the river] + の + [shopping street]

Here, 向こう means the other side or the far side.

In 川の向こう, it means the other side of the river.

Related words:

• 向こう = the other side / over there
• 向こう側 = the other side, often a little more explicit
• あちら = over there / that way, often more directional or polite

In this sentence, 向こう is a very natural choice because it refers to the far side of the river.

まで means up to, until, or as far as.

So:

• 商店街まで行く = go as far as the shopping street / go to the shopping street

It marks the destination as the endpoint.

Compare:

• 商店街に行く = go to the shopping street
• 商店街まで行く = go as far as the shopping street

In many cases both can work, but まで emphasizes the destination as the end point of movement.

Both ときは and ときに are possible in Japanese, but they do different things.

• とき = when / at the time of
• は after it marks that time as the topic
• に after it marks a specific time point for the action

Here:

• 行くときは、歩道橋を渡ります。 = When I go, as for that occasion, I cross the pedestrian overpass.

Using は gives a contrastive or topic-marking feel:

• When I go to the shopping street, I use the pedestrian overpass.

It can imply something like:

• When going there, I cross the overpass
  (maybe unlike some other situation)

If you said:

• 行くときに、歩道橋を渡ります。 that would also be understandable, but it feels more like at the time of going rather than setting up a general topic or condition.

Usually verb dictionary form + とき means when doing / when about to do that action, and the exact timing depends on context.

So:

• 行くとき usually means when I go / when I’m going
• It can sometimes include the idea of on the way to going or at the time of going

In this sentence, the natural interpretation is:

• When I go to the shopping street on the other side of the river, I cross the pedestrian overpass.

That means the crossing happens as part of that trip.

歩道橋 means a pedestrian overpass or footbridge, especially one built for people to walk across a road or similar obstacle safely.

It is made of:

• 歩道 = sidewalk / pedestrian path
• 橋 = bridge

So it is not just any bridge. It specifically suggests a bridge for pedestrians.

In this sentence, it probably means the speaker crosses using a pedestrian bridge rather than crossing at street level.

Great question. In Japanese, 渡る often takes を with the place being crossed.

So:

• 橋を渡る = cross the bridge
• 道を渡る = cross the road
• 川を渡る = cross the river

Even though it involves movement, Japanese treats the thing being crossed as the object of 渡る, so を is correct.

This is very common with some movement verbs:

• 道を歩く = walk along the road
• 空を飛ぶ = fly through the sky
• 橋を渡る = cross the bridge

So here:

• 歩道橋を渡ります = cross the pedestrian overpass

渡ります is the polite -ます form of 渡る.

• dictionary form: 渡る
• polite form: 渡ります

Japanese often uses the -ます form in neutral-polite statements, especially in textbooks, formal situations, or when speaking politely to someone.

The rest of the sentence matches that style:

• 行く is inside a modifying clause before とき, so it stays in plain form
• the main verb at the end is 渡ります, so that is where the politeness shows

This is normal Japanese grammar:

• subordinate clause: plain form
• main sentence ending: polite form

Because 行く is inside a clause modifying とき.

In Japanese, verbs before nouns or noun-like words such as とき usually appear in plain form, even in polite sentences.

So:

• 行くとき = when going
• 行ったとき = when went / when I went
• 行かないとき = when not going

The politeness of the whole sentence is usually shown at the very end, in the main verb:

• 歩道橋を渡ります

This is one of the most important patterns in Japanese:

• embedded/subordinate clause → plain form
• sentence-final predicate → shows politeness level

Yes. In this sentence, 行くときは is the topic-like part.

Structure:

• 川の向こうの商店街まで行くときは、 = when going to the shopping street on the other side of the river,
• 歩道橋を渡ります。 = I cross the pedestrian overpass.

The は marks the time/occasion of going there as the topic or frame for the statement.

So the sentence is something like:

• As for when I go to the shopping street on the other side of the river, I cross the pedestrian overpass.

This is a very common Japanese pattern:

• [situation/time/condition] は、[main statement]

Yes, that is a very natural interpretation.

Japanese present tense often covers:

• habitual actions
• general truths
• future actions, depending on context

So 渡ります here probably means a habitual action:

• When I go to that shopping street, I cross the pedestrian overpass.

It does not necessarily mean only one specific trip. It can easily describe what the speaker normally does.

Yes. 商店街 refers to a street or district lined with shops, often a local commercial area.

Possible translations include:

• shopping street
• shopping district
• shopping arcade (if covered, though this depends on the actual place)

The exact English choice depends on context, but shopping street is a very direct translation.

A helpful breakdown is:

• 川の向こうの商店街まで
  = up to / to the shopping street on the other side of the river
• 行くときは、
  = when going, / when I go,
• 歩道橋を
  = the pedestrian overpass
• 渡ります。
  = cross

So the full structure is:

[destination] + まで + [verb + とき + は], [object] + を + [main verb]

Or more simply:

When going to X, I do Y.

Here:

• X = the shopping street on the other side of the river
• Y = cross the pedestrian overpass