Denshi Jisho — Online Japanese dictionary

昨日 きのう yesterday
Common word, Adverbial noun, Temporal noun 
昨日 さくじつ yesterday
Common word, Adverbial noun, Temporal noun 
昨日今日 きのうきょう 1: yesterday and today;
2: (something that happened) only yesterday (just recently)
Noun 
昨日の今日 きのうのきょう right on the heels of yesterday, then today ...; soon after something, and yet now ...
Expression 
昨日の友は今日の敵 きのうのともはきょうのてき A friend today may turn against you tomorrow
Expression, Idiomatic expression 

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