konya tomodati to tuuwasimasu.

Japanese often leaves out the subject when it is obvious from context.

So 今夜 友達 と 通話します can naturally mean:

• I will call a friend tonight
• I’m having a voice call with a friend tonight

Even though I is not said, it is understood from the situation.

If you wanted to make it explicit, you could say:

• 私は今夜友達と通話します。

But in normal conversation, that often sounds unnecessary unless you are contrasting yourself with someone else.

Many time expressions in Japanese can be used without a particle.

So 今夜 works fine by itself in a sentence:

• 今夜友達と通話します。 = Tonight, I’ll call a friend.

This is similar to other common time words such as:

• 今日 = today
• 明日 = tomorrow
• 昨日 = yesterday

You can sometimes add は for emphasis or contrast:

• 今夜は友達と通話します。 = As for tonight, I’m calling a friend.

But you usually would not use に with 今夜 here.

Here, と marks the person you do the action with.

So:

• 友達と通話します = talk on the phone with a friend

This is a very common use of と.

Compare:

• 友達と話します = talk with a friend
• 友達と行きます = go with a friend
• 友達と勉強します = study with a friend

In this sentence, と does not mean and. It means with.

Because 友達 is not the direct object here. It is the person you are doing the call with, so it takes と.

Think of the phrase as one unit:

• 友達と = with a friend

If the sentence used a verb that took a direct object, then you might see を. But 通話する is normally used with the person marked by と.

通話します comes from:

• 通話 = a phone call / voice communication
• する = to do

So 通話する literally means to do a call, but in natural English it means something like:

• to talk on the phone
• to have a voice call
• to call someone

It sounds a bit more formal or technical than very casual everyday speech.

For example:

• 友達と通話します = fairly neutral/formal
• 友達と電話します = more everyday-sounding in many situations

It is understandable and correct, but it can sound a little more formal or specific than what learners may hear most often in casual conversation.

Native speakers might also say:

• 友達と電話します。
• 友達に電話します。
• 友達と電話で話します。

The nuance changes a little:

• 友達と通話します = have a call / be on a voice call
• 友達に電話します = call a friend
• 友達と電話します = talk by phone with a friend

So 通話します is fine, but it is not always the most casual everyday choice.

今夜 is pronounced こんや.

So the whole sentence is read:

• こんや ともだち と つうわします

In normal writing without beginner spacing:

• 今夜友達と通話します。

By itself, 友達 can mean friend or friends, depending on context.

So this sentence could mean:

• I’ll call a friend tonight
• I’ll call my friends tonight
• I’ll be on a call with friends tonight

If you want to make the plural clearer, you could say:

• 友達たちと通話します。 = I’ll call my friends / be on a call with friends

But Japanese often leaves number unspecified unless it matters.

Japanese normally puts the verb at the end of the sentence.

So the structure here is:

• 今夜 = tonight
• 友達と = with a friend
• 通話します = will have a call / call

This is a standard Japanese sentence pattern.

A rough word-for-word order is:

• Tonight / with a friend / will call

That may feel backward to an English speaker, but it is completely normal in Japanese.

Yes. A very natural version is:

• 今夜は友達と通話します。

Adding は makes 今夜 the topic, with a nuance like:

• As for tonight, I’m calling a friend
• Tonight, I’ll be on a call with a friend

Without は, the sentence is still fine and a bit more plain/direct.

通話します is in the polite non-past form.

That means it can mean:

• I call
• I will call
• I am going to call

depending on context.

Here, because 今夜 refers to the future, the sentence is understood as future:

• I’ll call a friend tonight

The plain form would be:

• 通話する

So:

• 今夜友達と通話する。 = plain/casual
• 今夜友達と通話します。 = polite

Yes. 通話 is broad enough to refer to voice communication, including things like:

• a regular phone call
• an app call
• an online voice call

That is one reason 通話 can sound a little more technical or general than 電話, which strongly suggests a telephone call.

So if the intended meaning is something like I’m going to voice chat with a friend tonight, 通話します can fit well.

The spaces are usually just for learners.

Normal Japanese writing would be:

• 今夜友達と通話します。

Japanese is normally written without spaces between words. Educational materials often add spaces to help beginners see the parts more clearly.