In the following sentence:
切符を買いたいんですが
I would like to buy a ticket.
What is the usage of が?
In the following sentence:
切符を買いたいんですが
I would like to buy a ticket.
What is the usage of が?
26.4.1.4 Clause1 ga. ( . . . ) in unfinished sentences
Sentences where S2 is left unsaid (implied) are commonly used, especially for introducing requests, to test the listener’s reaction, but also to imply that realization of S2 is not possible or realistic.
a) ちょっとすみませんが......。
Chotto sumimasen ga......
Excuse me.
b) ちょっとお伺いしたいんですが。
Chotto o-ukagai shitai n desu ga.
Could I ask you something?
c) 覚えていないんですが......。
Oboete inai n desu ga......
I don’t remember.
Source: Japanese: A Comprehensive Grammar. Routledge (2013)
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If you want an explanation in Japanese