がいやだった

was unpleasant; didn't like

→ が

phrase Common #7,461

was unpleasant; didn't like 嫌だった means “was unpleasant” or “didn't like.” Writing 嫌 as いや uses hiragana instead of kanji.

JA: 私は人前で話すのがいやだった。

EN: I didn't like speaking in front of people.