Interesting question.
For me,i also a student come to Singapore to study and don't know Chinese and my favorite is street photography (althought i'm not good at it)
You just take their photo and walk away. If they notice, give them your brightest smile. If they approach you,show them the photo and tell them u that u won't use the photo against their right like post one some *** forum :bsmilie: And please delete the photo if they ask u to do so,don't argue,respect them since it is their right to ask u to do that.
But don't be sneaky as well,just hold ur cam in ur hand,wrap the strap around ur wrist and walk around. When take photo,be quick,don't aim the cam at people too long,they will notice and feel uneasy.
Street photography for some is all about getting close and use wide lens, but be sure u don't invade their private zone which mean make them feel uncomfortable. Tele zoom also, if they notice,u look like doing some supicious things.
Just be normal --> u will look normal. Their is nothing wrong when taking people photo,be sure to smile. And if u can see on the subject face the uncomfortable,please change subject or wait for her (him) to stop paying attention to you :sweat:
Those are just my humble ideas.