watasitati ha oukyuuteate wo rensyuusuru.

When は is used as the topic particle, it is pronounced wa, not ha. This is one of the first pronunciation exceptions learners meet.

So:

• 私たちは = watashitachi wa
• not watashitachi ha

When は is part of a regular word, it is usually pronounced ha. But as a particle, it is pronounced wa.

Yes, 私たち means we or us, depending on context.

• 私 = I
• たち = a suffix that makes it plural in this kind of context

So 私たち literally means something like we.

That said, Japanese often leaves out subjects and topics when they are clear from context, so in real life you might hear just:

• 応急手当を練習する。

and the listener would understand who is doing it from the situation.

は marks the topic of the sentence. It tells the listener, as for us...

So:

• 私たちは = as for us / we

The rest of the sentence says something about that topic:

• 応急手当を練習する = practice first aid

So the whole structure is:

• As for us, [we] practice first aid.

In many beginner translations, this just becomes We practice first aid.

Both は and が can mark something like the English subject, but they do different jobs.

• は marks the topic
• が marks the subject more directly and often sounds more specific, more contrastive, or more like new information

In this sentence, 私たちは応急手当を練習する sounds like a neutral statement about us as the topic.

If you said 私たちが応急手当を練習する, it could sound more like:

• We are the ones who practice first aid
• or It is we who will practice first aid

So は is the more natural default here unless you specifically want that emphasis.

Yes, 応急手当 is a noun meaning first aid or emergency treatment.

It is read:

• おうきゅうてあて (oukyuu teate)

It is made from:

• 応急 = emergency / temporary / urgent response
• 手当 = treatment / care / attending to

Together, they form the set phrase 応急手当, which means first aid.

を marks the direct object of the verb.

Here, the verb is:

• 練習する = to practice

So the thing being practiced is marked with を:

• 応急手当を練習する = to practice first aid

This is very similar to English word order, except Japanese uses a particle instead of relying mainly on position.

Japanese normally puts the verb at the end of the sentence. This is one of the biggest differences from English.

English:

• We practice first aid.

Japanese:

• 私たち は 応急手当 を 練習する。
• literally: We / topic / first aid / object / practice

A very common basic pattern is:

• Topic + object + verb
• or more generally, everything comes before the verb

So seeing the verb at the end is completely normal in Japanese.

練習する is the dictionary form or plain form of the verb.

• 練習する = plain form
• 練習します = polite form

Both can mean practice or will practice, depending on context.

So:

• 私たちは応急手当を練習する。 = plain style
• 私たちは応急手当を練習します。 = polite style

Textbooks often use the plain form when introducing grammar or vocabulary because it is the base form of the verb.

Yes. 練習 is a noun meaning practice, and adding する turns it into a verb:

• 練習 = practice
• 練習する = to practice

This is a very common pattern in Japanese. Many nouns can combine with する to make verbs.

Examples:

• 勉強する = to study
• 運動する = to exercise
• 説明する = to explain

So 練習する is a very standard noun + する verb.

It is understandable and grammatically fine, but in real Japanese, many speakers would more naturally say:

• 応急手当の練習をする

This literally means do practice of first aid.

The difference is small:

• 応急手当を練習する = practice first aid
• 応急手当の練習をする = do first-aid practice / practice first aid

Both work, but the A の 練習をする pattern is very common when talking about practicing a skill or activity.

Not necessarily. The plain non-past form 練習する can mean:

• practice
• will practice
• sometimes a general/habitual action

So depending on context, it could mean:

• We practice first aid
• We will practice first aid

If you want to clearly say we are practicing first aid now, you would usually use:

• 私たちは応急手当を練習している。
• or politely: 私たちは応急手当を練習しています。

The spaces are just for learners. Normal Japanese writing usually does not use spaces between words.

So a natural written version would be:

• 私たちは応急手当を練習する。

Beginner materials often add spaces to make the sentence structure easier to see.