shícái zài bīngxiāng lǐ.

In Mandarin, 在 often does the job that is/are in/at/on does in English when you are talking about location.

So:

食材在冰箱里。
literally follows the pattern:

thing + 在 + place

That is enough to mean The ingredients are in the fridge.

You do not need a separate verb like 是 here. In fact, 是 is generally not used for location in this kind of sentence.

• Correct: 食材在冰箱里。
• Not natural: 食材是冰箱里。

食材 means food ingredients or cooking ingredients.

It usually refers to ingredients used to prepare a meal, such as vegetables, meat, tofu, mushrooms, and so on.

It is a bit more specific than:

• 食物 = food
• 东西 = things/stuff
• 材料 = materials

So if you mean ingredients for cooking, 食材 is a very good word.

Here, 在 marks location. It tells you where something is.

In this sentence:

食材 在 冰箱里。
= The ingredients are in the fridge.

A very common pattern is:

A 在 B
= A is at/in/on B

Examples:

• 书在桌子上。 = The book is on the table.
• 猫在椅子下面。 = The cat is under the chair.

So in your sentence, 在 connects 食材 with its location.

里 means inside or in.

Since a fridge is a container-like place, Mandarin usually says:

• 冰箱里 = in the fridge
• literally: fridge-inside

So:

食材在冰箱里。
= The ingredients are in the fridge.

This is very common with nouns that are places or containers:

• 房间里 = in the room
• 包里 = in the bag
• 车里 = in the car

Usually, 冰箱里 is better and more natural.

Because a fridge is something with an inside, Mandarin normally uses 里 to make the location clear:

• 食材在冰箱里。 = natural
• 食材在冰箱。 = usually sounds incomplete or less natural

With some place words, Mandarin can omit words like 里, 上, or 下 in certain contexts, but for 冰箱, learners should strongly prefer 冰箱里.

The pattern is:

noun + 在 + place + location word

So here:

• 食材 = the ingredients
• 在 = are located at/in
• 冰箱里 = in the fridge

Full structure:

食材在冰箱里。

This is the normal way to say where something is.

A simple formula is:

Thing + 在 + Place

Examples:

• 手机在包里。 = The phone is in the bag.
• 牛奶在桌子上。 = The milk is on the table.

Yes, but the meaning and focus are slightly different.

• 食材在冰箱里。 = The ingredients are in the fridge.
  Focus: where the ingredients are

• 冰箱里有食材。 = There are ingredients in the fridge.
  Focus: what is in the fridge

So both are correct, but they answer different kinds of questions:

• 食材在哪儿？ → 食材在冰箱里。
• 冰箱里有什么？ → 冰箱里有食材。

Both can mean inside.

• 冰箱里
• 冰箱里面

Both are correct here.

里面 is slightly fuller or more explicit, while 里 is shorter and very common in everyday speech.

So these are both fine:

• 食材在冰箱里。
• 食材在冰箱里面。

For a beginner, it is good to learn 里 first, since it appears in many basic sentences.

No, not in this sentence.

Classifiers are needed when you are counting or using demonstratives like this/that:

• 这些食材 = these ingredients
• 那些食材 = those ingredients

But when 食材 is just the subject by itself, no classifier is needed:

• 食材在冰箱里。

If you wanted to be more specific, you could say:

• 这些食材在冰箱里。 = These ingredients are in the fridge.

It can be understood as either ingredient(s) depending on context, but in practice it often feels plural in English translation: ingredients.

Mandarin nouns usually do not change form for singular vs. plural the way English nouns do.

So:

• 食材 could mean ingredient or ingredients
• context tells you which one is meant

In this sentence, English will often translate it as The ingredients are in the fridge.

If you want to clearly mark plurality with these/those, you can say:

• 这些食材在冰箱里。

The pinyin is:

shícái zài bīngxiāng lǐ

Tones:

• 食 shí — 2nd tone
• 材 cái — 2nd tone
• 在 zài — 4th tone
• 冰 bīng — 1st tone
• 箱 xiāng — 1st tone
• 里 lǐ — 3rd tone

A rough pronunciation guide:

• shícái = shrr-tsai (with rising tones)
• zài = a sharp falling tone
• bīngxiāng = two high level tones
• lǐ = low dipping tone

Try to say it smoothly as one phrase:

shícái zài bīngxiāng lǐ

You can, but 冰箱里 is much more natural in everyday speech.

• 里 = common, conversational
• 内 = more formal or written

So:

• 食材在冰箱里。 = normal everyday Mandarin
• 食材在冰箱内。 = understandable, but more formal or stiff

For daily conversation, use 里.

Yes, but it changes the emphasis.

Normal order:

• 食材在冰箱里。

Location-first versions are possible in certain contexts, especially when emphasizing the place:

• 冰箱里有食材。 = There are ingredients in the fridge.
• 在冰箱里的是食材。 = What is in the fridge is ingredients.
  This is much more marked and less basic.

For beginners, the simplest and most useful pattern is still:

食材在冰箱里。

冰箱 is the normal everyday word for refrigerator / fridge.

In English, fridge sounds more casual and refrigerator sounds more formal, but Mandarin usually just uses 冰箱 for both.

So depending on the English style, the sentence can be translated as either:

• The ingredients are in the fridge.
• The ingredients are in the refrigerator.

Both are fine.