Предварительная стирка показала: эта ткань линяет.

Because it describes стирка, and стирка is a feminine noun.

So the phrase is:

• предварительная = preliminary / pre-
• стирка = washing / wash

Since the noun is feminine singular nominative, the adjective must match it:

• masculine: предварительный
• feminine: предварительная
• neuter: предварительное

This is basic adjective–noun agreement in Russian.

Literally, it means preliminary washing or a preliminary wash.

In natural English, depending on context, it could mean:

• a test wash
• a pre-wash
• preliminary washing

Here it sounds like someone washed the fabric first in order to check how it behaves, and that wash revealed a problem.

Because it is the subject of the verb показала.

The structure is:

• Предварительная стирка = the preliminary wash
• показала = showed / revealed

So: The preliminary wash showed/revealed ...

Subjects are normally in the nominative case in Russian.

In the past tense, Russian verbs agree with the subject in gender and number.

Since стирка is:

• feminine
• singular

the past tense must also be feminine singular:

• показал = masculine
• показала = feminine
• показало = neuter
• показали = plural

So стирка показала is the correct agreement.

The colon introduces the content of what was shown or revealed.

So this sentence is roughly:

• The preliminary wash showed: this fabric runs/fades.

In English, we would often use that instead:

• The preliminary wash showed that this fabric runs.

Russian can also use что:

• Предварительная стирка показала, что эта ткань линяет.

That version is also very natural. The version with the colon feels a bit more concise, report-like, or label-like.

Yes, absolutely:

• Предварительная стирка показала, что эта ткань линяет.

This is probably the most straightforward everyday version.

The difference is mostly stylistic:

• with что → standard, neutral sentence
• with a colon → more compact, sometimes more formal, technical, or written-report style

Both are correct.

Here линяет means that the fabric loses dye, runs, or fades in the wash.

For fabric, common English translations are:

• the fabric runs
• the dye runs
• the fabric bleeds color
• the fabric fades

The exact English choice depends on context, but the basic idea is that washing causes the color to come out or weaken.

The dictionary form is линять.

In this sentence:

• линяет = 3rd person singular, present tense
• literally: (it) runs/fades/sheds color

Because the subject is эта ткань (this fabric), Russian uses the singular verb:

• эта ткань линяет = this fabric runs/fades

This is very natural in Russian.

The first part refers to a past event:

• Предварительная стирка показала = The preliminary wash showed

The second part states a current or general property of the fabric:

• эта ткань линяет = this fabric runs/fades

So the meaning is not it was fading at that exact moment, but rather it turns out this fabric is the kind that runs/fades.

English does something similar:

• The test showed that this fabric fades.

So the present tense here expresses a general fact.

Because ткань is a feminine noun.

The demonstrative this must agree with the noun:

• masculine: этот
• feminine: эта
• neuter: это

So:

• эта ткань = this fabric

Even though the noun ends in a soft sign (ь), it is feminine, and that is why эта is used.

Nouns ending in ь can be either masculine or feminine, so you often have to learn the gender with the word.

For ткань, the gender is feminine. You can see that from agreement:

• эта ткань
• новая ткань
• ткань линяет

There is no universal rule that all -ь nouns are one gender, so for words like this, memorizing the gender is important.

No. Линять has a broader meaning connected with losing color or shedding.

It can be used for:

• fabric losing dye
• clothes fading
• animals shedding fur or feathers

So the core idea is something like to lose outer covering/color.

In this sentence, because the subject is ткань, the meaning is specifically about the color running or fading.

No, Russian does not need an object here.

Ткань линяет is a complete sentence and sounds natural by itself.

Russian can express the idea without explicitly saying color. The listener understands that the fabric is losing dye or fading.

So while English often says:

• the fabric bleeds color

Russian naturally says simply:

• ткань линяет

Literally, эта ткань means this fabric.

It usually points to a specific fabric being discussed or tested. For example:

• this particular cloth
• this material here
• this batch/type of fabric in context

In English, depending on the situation, you might translate it as:

• this fabric
• the fabric

Russian often includes эта when referring to something concrete and already present in the situation.

The word order is very normal.

• Предварительная стирка показала = the preliminary wash revealed
• эта ткань линяет = this fabric runs/fades

Russian word order is more flexible than English, but this version is neutral and clear.

You could rearrange parts for emphasis, but the given sentence sounds natural, especially in a factual or descriptive context.

The stresses are:

• предварИтельная
• стИрка
• показАла
• Эта
• ткАнь
• линЯет

A rough pronunciation guide:

• pred-va-rí-tel-na-ya stír-ka pa-ka-ZA-la: É-ta tkan' li-NYA-yet

For learners, the most important stress to notice is линЯет, because it may not be where an English speaker expects it.

It sounds a bit more written or report-like, especially because of the colon.

You might see something like this in:

• product notes
• fabric testing results
• a care description
• a warning or quality comment

A more conversational version might be:

• Предварительная стирка показала, что эта ткань линяет.

That said, the original sentence is completely natural Russian.