✔ 最佳答案
how many mtr stations are there now?
這句話除了首字(How)用大寫及mtr應是MRT的筆誤,看不出文法有錯.
另How many people now take the MRT? “now” 是什意思感覺很模糊,改成How many people take the MRT each day? 感覺意思清晰些.
另How long can we use wifi? (Wireless Fidelity) 如要寫的正式些,感覺上還是該用WiFi或WIFI,不過話說回來我看英文網站小寫的wifi也用得很普遍 )