जब तक कमीज़ गीली है, तब तक उसे ड्रायर में रखिए।

This is a very common Hindi pair used to talk about a time limit or condition.

• जब तक = as long as / until
• तब तक = until then / for that long

So the overall pattern means something like:

as long as X is true, do Y

In this sentence, it gives the idea:

while the shirt is wet, put/keep it in the dryer

Depending on context, English may translate it as as long as or until.

Not always.

You will often hear:

जब तक कमीज़ गीली है, उसे ड्रायर में रखिए।

That is perfectly normal. Adding तब तक makes the relationship more explicit and slightly more emphatic:

जब तक ..., तब तक ...

So:

• जब तक ... alone = common and natural
• जब तक ..., तब तक ... = a bit fuller, more balanced, often clearer

Hindi does not have articles like a, an, and the.

So कमीज़ can mean:

• a shirt
• the shirt

The exact meaning comes from context. In this sentence, the context makes it clear that we mean a specific shirt, so English naturally uses the shirt.

Because कमीज़ is a feminine noun in Hindi.

The adjective गीला / गीली / गीले changes to agree with the noun:

• masculine singular: गीला
• feminine singular: गीली
• plural: often गीले / गीली depending on structure and style

So:

• कपड़ा गीला है = the cloth is wet
• कमीज़ गीली है = the shirt is wet

This is basic gender agreement.

Here उसे means it, referring back to कमीज़.

A useful thing to remember is that Hindi third-person pronouns do not work like English he/she/it. The same form can mean:

• him
• her
• it

depending on context.

So in this sentence:

उसे ड्रायर में रखिए = put it in the dryer

You could also hear उसको instead of उसे. In everyday Hindi, those are often interchangeable.

For the same reason English often says the shirt ... put it in the dryer instead of repeating the shirt again. Hindi also commonly avoids repetition with a pronoun.

So both are possible:

• जब तक कमीज़ गीली है, तब तक उसे ड्रायर में रखिए।
• जब तक कमीज़ गीली है, तब तक कमीज़ को ड्रायर में रखिए।

The version with उसे sounds more natural and less repetitive.

में means in / inside.

So:

• ड्रायर में = in the dryer

Hindi normally uses में with containers, rooms, machines, and enclosed spaces. English may say put it in or put it into, but Hindi usually just uses में here.

So:

उसे ड्रायर में रखिए = put/keep it in the dryer

रखिए is the polite imperative of रखना (to put, place, keep).

It is used when speaking politely, especially with आप.

Compare:

• रखो = informal
• रखिए = polite
• रखिये = alternative spelling you may also see

So रखिए is like saying:

• put it
• keep it
• please place it

in a polite way.

It can mean either, depending on context.

The verb रखना has a broad meaning: to put, place, keep, leave.

So this sentence could be understood as:

• put it in the dryer
• keep it in the dryer

If you want to make keep it there more explicit, Hindi can use additional wording, but रखिए by itself often covers both ideas.

Yes—at least in the sense that it is a very normal loanword in modern Hindi.

Hindi uses many English loanwords for everyday objects, especially technology and appliances. So ड्रायर sounds natural in ordinary speech.

A more purely descriptive Hindi expression would be something like:

कपड़े सुखाने की मशीन

But in real life, ड्रायर is much more likely.

It is understandable, but there is a nuance.

The sentence you have literally focuses on the state:

the shirt is wet

So it feels like:

as long as the shirt is wet, keep/put it in the dryer

If you want to emphasize the endpoint until it becomes dry, many speakers would prefer:

जब तक कमीज़ सूख न जाए, उसे ड्रायर में रखिए।

That means more specifically:

keep it in the dryer until the shirt dries

So the original is fine, but सूख न जाए is often more precise if the goal is until it dries.