haha ha zyuuzi ni nemasu.

My mother goes to bed at ten o'clock.

Breakdown of haha ha zyuuzi ni nemasu.

• は: topic particle
• に: time particle
• 母はは: mother
• 寝ねる: to sleep
• 十時じゅうじ: ten o'clock

Questions & Answers about haha ha zyuuzi ni nemasu.

Why is the particle は used after 母 instead of が?

The particle は marks 母 (mother) as the topic of the sentence—the thing we’re talking about—rather than simply marking it as the grammatical subject. If you used が, you’d be focusing on “mother” as new or important information (“It’s my mother who …”), whereas は gives a more general statement: “As for my mother, she goes to bed at ten.”

Why do we need the particle に after 十時?

に is the time-marking particle used with exact times. Whenever you specify a clock time like 一時 (1:00), 三時半 (3:30), or 十時 (10:00), you attach に to mean “at [that time].” Without に it sounds incomplete or unusual (unless in some set expressions).

Why is 寝ます used instead of 寝る?

寝る is the plain (dictionary) form meaning “to sleep/go to bed.” 寝ます is the polite non-past form (present/future/habitual). You use ～ます endings in polite or formal speech. In casual situations you’d say 寝る instead, but the basic meaning is the same.

How are 母 and 十時 pronounced?

• 母 is read はは when you refer to your own mother; when talking to or about someone else’s mother you usually say お母さん (おかあさん).
• 十時 is read じゅうじ. If you need to specify AM/PM you can say 午前十時 (ごぜんじゅうじ, 10 AM) or 午後十時 (ごごじゅうじ, 10 PM).

Does this sentence imply a one-time action tonight or a habitual action?

By itself, 母は十時に寝ます uses the non-past form, which can express: • A habitual action (“My mother goes to bed at ten every night.”)
• A future action (“My mother will go to bed at ten [tonight].”)

To make it clearly habitual add 毎晩 (まいばん, “every night”):
　母は毎晩十時に寝ます。
To pinpoint a single upcoming event add 今夜 (こんや, “tonight”):
　今夜母は十時に寝ます。

Why isn’t there any object marked with を in this sentence?

寝る is an intransitive verb in Japanese (“to sleep/go to bed”) and does not take a direct object. You don’t “sleep something,” so no を is used. The person doing the action is marked with は or が, and the time is marked with に.

Can you omit 母は or 十時に in this sentence?

Yes. If context makes them clear you can drop:

• 母は → 十時に寝ます。 (“(She/He) goes to bed at ten.”)
• 十時に → 母は寝ます。 (“My mother goes to sleep.”)

Japanese often omits subjects or time expressions when they’re understood.

Could I use the plain form instead of the polite form here?

Absolutely. In casual speech you’d say 母は十時に寝る。 It’s the same structure, just using the plain ～る ending instead of the polite ～ます ending.