wǒ yào zhíjī
I need to check in for a flight
登机口在哪里?
Where is the departure gate?
登机口 (dēngjīkǒu) means "boarding gate," 在 (zài) is "to be at," and 哪里 (nǎlǐ) is "where." The structure is "[place] is where?"
请问登机口在哪里?
qǐngwèn dēngjīkǒu zài nǎlǐ?
Excuse me, where is the boarding gate? — More polite because of '请问' (excuse me).
登机口在哪?
dēngjīkǒu zài nǎ?
Where's the boarding gate? — Shorter, without '里'.
请问登机口在哪里?
qǐngwèn dēngjīkǒu zài nǎlǐ?
Excuse me, where is the boarding gate?
登机口在二楼。
dēngjīkǒu zài èr lóu.
The boarding gate is on the second floor.
Appropriate
Avoid when
You say '登机口在哪里?' (dēngjīkǒu zài nǎlǐ?).
It is pronounced 'dēngjīkǒu zài nǎlǐ?' with the tones: dēng (1st tone), jī (1st tone), kǒu (3rd tone), zài (4th tone), nǎ (3rd tone), lǐ (3rd tone).
Use it at the airport when you need to find your departure gate. It is a direct and polite question suitable for asking staff or other travelers.
Tomyo
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