shìyījiān zài nǎlǐ?
Where is the fitting room?
可以试穿吗?
Can I try it on?
This is a polite question formed with 可以 (kěyǐ, 'may/can'), the verb 试穿 (shìchuān, 'to try on'), and the question particle 吗 (ma).
可以试试吗?
kěyǐ shìshì ma?
Can I try? — More casual, used for trying anything, not just clothes.
我可以试穿吗?
wǒ kěyǐ shìchuān ma?
May I try it on? — More polite, explicitly includes 'I'.
请问,我可以试穿吗?
qǐngwèn, wǒ kěyǐ shìchuān ma?
Excuse me, may I try it on?
当然可以,试衣间在那边。
dāngrán kěyǐ, shìyījiān zài nàbiān.
Of course, the fitting room is over there.
Appropriate
Avoid when
You say 可以试穿吗? (kěyǐ shìchuān ma?). This is the standard polite way to ask in a shop.
It is pronounced kěyǐ shìchuān ma? The tones are: kě (3rd), yǐ (3rd), shì (4th), chuān (1st), ma (neutral).
Use it when you are in a clothing or shoe store and want to try on an item. It is polite and appropriate for any customer.
Tomyo
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