zhège nánrén zài yòng xǐyījī.

Here, 在 is marking an action that is in progress.

So:

• 用 = to use
• 在用 = to be using

That makes the sentence mean something like This man is using the washing machine.

This is a very common pattern in Mandarin:

• 他在吃饭。 = He is eating.
• 我在看书。 = I am reading.

You can think of 在 + verb as often working like English be + -ing.

Not in this sentence.

在 has more than one use in Mandarin:

1. As a location word/verb:

   • 他在家。 = He is at home.

2. As a progressive marker before a verb:

   • 他在吃饭。 = He is eating.

In 这个男人在用洗衣机, 在 comes before the verb 用, so it is the progressive marker, not a location word.

Because Mandarin does not use 是 the way English uses is before action verbs.

In English, you say:

• He is using...

In Mandarin, you do not say:

• 他是在用... for a normal sentence like this

Instead, you say:

• 他在用...

So the idea of is using is expressed by 在 + verb, not by adding a separate is verb.

Because in standard Mandarin, demonstratives like 这 and 那 usually need a measure word before a noun.

So:

• 这 + 个 + 男人
• 这个男人 = this man

Here, 个 is the measure word.

Saying 这男人 can happen in casual speech or certain styles, but 这个男人 is the normal standard form learners should use.

Yes.

In 这个男人:

• 这 = this
• 个 = general measure word
• 男人 = man

So 这个男人 literally follows the common Chinese pattern:

• demonstrative + measure word + noun

Examples:

• 这个人 = this person
• 那个老师 = that teacher
• 这本书 = this book

Even though 个 is often taught as the most general measure word, it is still a real measure word here.

The basic order is:

Subject + 在 + Verb + Object

So here:

• 这个男人 = subject
• 在 = progressive marker
• 用 = verb
• 洗衣机 = object

Altogether:

• 这个男人 在 用 洗衣机。

This is a very normal Mandarin sentence pattern.

用 means to use.

So 用洗衣机 literally means to use a washing machine.

In context, this could mean:

• he is operating the washing machine
• he is using the washing machine to do laundry

If you want to be more explicit and say he is washing clothes with it, you could say:

• 这个男人在用洗衣机洗衣服。 = This man is using the washing machine to wash clothes.

But the original sentence is still natural if the picture or context already makes things clear.

No.

Even though 在 can relate to location in other sentences, that is not what is happening here.

In this sentence, 在 is followed by the verb 用, so it marks an ongoing action:

• 在用 = is using

If you wanted to say The man is in the washing machine, the sentence structure would be completely different, such as:

• 这个男人在洗衣机里。

Here:

• 在...里 = in...

So the grammar makes the meaning clear.

Yes, absolutely.

正在 also marks an action in progress, often with a slightly stronger sense of right now.

So these are both natural:

• 这个男人在用洗衣机。
• 这个男人正在用洗衣机。

Very roughly:

• 在用 = is using
• 正在用 = is currently using / is right in the middle of using

Both are correct.

In this sentence, 男人 simply means man or adult male.

That is the normal meaning here.

In some colloquial contexts, 男人 can sometimes refer to someone’s husband or male partner, but that is not the default meaning in a sentence like this.

So for this sentence, just understand it as:

• 这个男人 = this man

Yes, it is natural.

It is especially natural if the context is a picture or a description of what someone is doing right now.

Depending on what you want to emphasize, Mandarin speakers might also say:

• 这个男人在洗衣服。 = This man is washing clothes.
• 这个男人在用洗衣机洗衣服。 = This man is using the washing machine to wash clothes.

But 这个男人在用洗衣机。 is perfectly fine if the point is specifically that he is using the washing machine.

In careful pronunciation, it is usually given as zhège.

In everyday speech, many speakers say something closer to zhèige.

So as a learner:

• zhège is the standard textbook form
• zhèige is a very common spoken pronunciation

Both are useful to recognize when listening.