kěyǐ yòng jiāotōng kǎ ma?
Can I pay with a transport card?
二号线换一号线。
Transfer from the second line to the first
The phrase is built as: 二号线 (èr hào xiàn, 'line 2') + 换 (huàn, 'to transfer/change') + 一号线 (yī hào xiàn, 'line 1'). The structure is [line A] + 换 + [line B], meaning 'transfer from A to B'.
换乘一号线
huàn chéng yī hào xiàn
Transfer to line 1 — More formal, often used in announcements or signs.
二号线换到一号线
èr hào xiàn huàn dào yī hào xiàn
Transfer from line 2 to line 1 — More colloquial, with an explicit 'to'.
请问,怎么去一号线?
qǐng wèn, zěn me qù yī hào xiàn?
Excuse me, how do I get to line 1?
你需要在二号线换一号线。
nǐ xū yào zài èr hào xiàn huàn yī hào xiàn.
You need to transfer from line 2 to line 1.
Appropriate
Avoid when
You say 二号线换一号线 (èr hào xiàn huàn yī hào xiàn).
It's pronounced èr hào xiàn huàn yī hào xiàn. Pay attention to the tone change: 一 (yī) is first tone here, but in some contexts it changes.
Use 换 when you change from one metro line to another. For example, 二号线换一号线 means 'transfer from line 2 to line 1'.
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