I had almost decided to keep my rendezvous with Tony...
I decided to play football 表示當下決定去踢球...
3、decide用作及物動詞表示“決定”“決心”時,可接名詞、代詞、動詞不定式、帶疑問詞的動詞不定式或虛擬的名詞從句作賓語...