昨夜（ゆうべ）— last night
昨夜 は 寝たくなかった です。
I didn’t want to go to bed last night.
昨夜ゆうべ
last night
ゆうべ
accent [3]In detail
Words
昨夜yūbelast night
はwa(topic marker)
寝たくなかったnetakunakattadid not want to go to bed
ですdesu(polite sentence ending)
Kanji
昨サクyesterday; previous
夜ヤ・
昨夜 is read ゆうべ here. It can also be read さくや. Both refer to last night, with さくや often sounding more formal.
Coco-sensei