YOU SAID:
What time do you go to bed at night?
INTO JAPANESE
昨晩何時に寝ましたか。
BACK INTO ENGLISH
What time do you go to bed last night?
INTO JAPANESE
昨晩何時に寝ましたか。
BACK INTO ENGLISH
What time do you go to bed last night?
That didn't even make that much sense in English.