Here some basic Mandarin phrases you might find useful:
Yes = shr 是
No = bu shr 不是
Thank you = shie shie 謝謝
Thank you very much = fei chang gan shie / hen gan shie 非常感謝 / 很感謝
You're welcome = bu yung shie 不客氣
Please = ching 請
Excuse me = duei bu chi 對不起
Hello = ni hau 你好
Goodbye = tzai jian 再見
Good morning = tzau an 早安
Good afternoon = wu an 午安
Good evening = wan shang hau 晚上好
Good night = wan an 晚安
Do you speak ... = ni huei jiang ... ma? 你會講...嗎？
English = ying yu 英語
I = wo 我
We = wo men 我們
You (singular, familiar) = ni 你
You (singular, formal) = nin 您
You (plural) = ni men 你們
He/She = ta 他 / 她
They = ta men 他們
Where is the bath room? = shi shou jian tzai na li? 洗手間在哪裡?
How are you? = ni hau ma? 你好嗎？
How much does this cost? = je duo shau chian? 這多少錢？
Do you accept credit cards? = ni jie shou shin yung ka ma? 你接受信用哪嗎？
I'll buy it. = wo yau mai 我要買
Please bring the bill. = mai dan 買單
Bread = mian bau 麵包
Coffee = ka fei 咖啡
Tea = cha 茶
Juice = guo jr 果汁
Water = shuei 水
Beer = pi jiou 啤酒
Wine = jiou 紅酒
Meat = rou 肉
Beef = niou rou 牛肉
Pork = ju rou 豬肉
Fish = yu 魚
Vegetable = shu tsai 蔬菜
Fruit = shuei guo 水果
Salad = sha la 沙拉
Dessert = dian shin 點心
How much is the fare? = che piau duo shau qian? 車票多少錢？
Ticket = piau 票
Train = huo che 火車
Bus = gung che 公車
Subway, Underground = jie yun 捷運
Airport = ji chang 機場
Train station = huo che jan 火車站
Bus stop = gung che jan 公車站
Subway station, Underground station = jie yun jan 捷運站
