wǒ zài wǎngshàng chá yíngdì.

在 introduces the place or medium where the action happens.

In this sentence, 在网上 means on the internet / online. Mandarin often puts this kind of location phrase before the main verb:

• 我在网上查营地
• literally: I + online + search + campsites

So 在 is not the main verb here. It is marking the setting for 查.

In Mandarin, place/location phrases usually come before the main verb, not after it as often happens in English.

A common pattern is:

Subject + 在 + place + verb + object

So:

• 我在网上查营地 is natural.
• 我查营地在网上 sounds unnatural in normal speech.

English often says something like I search for campsites online, with online near the end. Mandarin usually places that information earlier.

网上 means online / on the internet.

It is made up of:

• 网 = net / network / internet
• 上 = on / above / upper part

So literally it is something like on the net.

This is similar to other location expressions in Chinese:

• 桌上 = on the table
• 墙上 = on the wall
• 路上 = on the road

In modern Chinese, 网上 is a very common way to say online.

Because 网上 is not a possessive phrase. It is a fixed location expression.

Learners sometimes expect something like 网的上, but that is not how Chinese works here. The pattern is simply:

noun + 上 / 下 / 里 / 外

Examples:

• 桌上 = on the table
• 书里 = in the book
• 门外 = outside the door
• 网上 = online

So 网上 is the normal form.

Not exactly. 查 has a broader meaning than English search. It can mean:

• to look up
• to check
• to investigate
• to search for information

In this sentence, 查 works well because you are looking up information about campsites online.

Related words:

• 找 = look for, try to find
• 搜索 = search, especially in a search-engine or technical sense
• 查找 = look up / search for

So 查营地 suggests checking or looking up campsite information, not just physically hunting for one.

营地 usually means camp site, campground, camp, or base camp, depending on context.

It can be used in different situations:

• outdoor camping
• military camps
• temporary bases

If the context is specifically recreational camping, sometimes 露营地 is even clearer, because 露营 means camping.

So:

• 营地 = camp site / camp area / base
• 露营地 = campsite / campground for camping

Mandarin does not use articles like a or the the way English does.

So 营地 by itself can mean:

• a campsite
• the campsite
• campsites

The exact meaning depends on context.

Chinese also often leaves number unspecified unless it matters. If you want to be specific, you can add something like:

• 一个营地 = one campsite
• 那个营地 = that campsite
• 一些营地 = some campsites

But in a general sentence like this, the bare noun 营地 is completely normal.

By itself, it does not clearly mark tense the way English does.

我在网上查营地 can mean different things depending on context, such as:

• I’m looking up campsites online.
• I look up campsites online.
• I’ll look up campsites online.

Mandarin often relies on context and time words instead of verb tense endings.

If you want to make it more clearly right now, you could say:

• 我正在网上查营地 = I’m looking up campsites online right now.

If you want to mark completed action:

• 我在网上查了营地 = I looked up campsites online.

Because 是 is not used before ordinary action verbs like 查.

是 is mainly used to link one noun to another, like A is B:

• 我是学生 = I am a student.

But in 我在网上查营地, the main verb is 查, an action verb. So adding 是 would be incorrect.

Yes. There are several natural alternatives, with slightly different tones or styles:

• 我上网查营地。
  This means I go online to look up campsites. Very common in speech.

• 我在网络上查营地。
  More formal than 网上.

• 我在网上查找营地。
  Slightly more explicit: look up / search for campsites online.

Among these, 在网上 is very natural and common.

To negate it, use 不 before the verb phrase:

• 我不在网上查营地。 = I do not look up campsites online.

To make a yes/no question, add 吗:

• 我在网上查营地吗？
  Grammatically possible, but usually this means Am I looking up campsites online?, which is not the most natural question unless you are checking what someone is doing.

More naturally, you might ask another person:

• 你在网上查营地吗？ = Are you looking up campsites online?

Or use the A-not-A pattern:

• 你在网上查不查营地？ = Do you look up campsites online?

In Chinese writing, characters are not separated by spaces the way English words are, so this question is a little tricky.

网上 consists of two characters:

• 网
• 上

Together they function as a set expression meaning online.

So from a learner’s point of view, it is helpful to remember 网上 as one unit of meaning, even though it is made of two characters.

查营地 is understandable and fairly natural, especially in context. But native speakers often make it more specific depending on what they mean.

For example:

• 查营地信息 = look up information about campsites
• 查露营地 = look up campsites
• 查附近的营地 = look up nearby campsites

So your sentence is fine, but in real conversation people often add more detail if needed.