Breakdown of tosyokan de ha koe wo sagete kudasai.
はha
topic particle
をwo
direct object particle
でde
location particle
図書館tosyokan
library
くださいkudasai
please
声koe
voice
下げるsageru
to lower
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Questions & Answers about tosyokan de ha koe wo sagete kudasai.
Why is 図書館で used here instead of 図書館に?
In Japanese, で marks the location where an action takes place. Lowering your voice is an action, so we use 図書館で (“at/in the library”). If you used に, it would more often indicate a destination or existence (“to the library” or “in the library” for a stative verb), which doesn’t fit here.
What’s the function of the は in 図書館では?
Here では combines two particles: で (location of action) + は (topic marker). By saying 図書館では, you set “in the library” as the topic or context (“As for in the library…”), highlighting that this rule applies specifically there.
Why is 声を下げてください used instead of 声を小さくしてください or other verbs?
- 声を下げる literally means “to lower one’s voice,” a common set phrase for speaking more quietly.
- 声を小さくする (“make your voice small”) is understandable but less idiomatic.
- Other verbs like 声を抑える or 声を潜める have nuances of suppressing or whispering and may sound more formal or literary.
What kind of request form is 〜てください?
〜てください is the polite imperative/request form. You take the て-form of a verb (here 下げる → 下げて) and attach ください, turning it into “please do ….” It’s softer than the plain imperative (下げろ).
Why is there no subject in this sentence? Who is being asked to lower their voice?
Japanese often omits the subject when it’s clear from context. This is a public instruction, so the implied subject is “everyone” or “you” (the reader/listener). In English you’d supply “you,” but in Japanese it stays unspoken.
Is it okay to omit は and just write 図書館で声を下げてください?
Yes. Dropping は leaves you with 図書館で声を下げてください which still means “Please lower your voice in the library.” Without は, it’s a straightforward instruction without the topical emphasis.
Could I instead say 図書館では静かにしてください to express the same idea?
Absolutely. 静かにしてください (“please be quiet”) is very common on signs. It’s a bit more general—it asks for overall quiet behavior, not just lowering one’s voice—but in practice they’re interchangeable in a library context.