看來沒有問題...
"I overheard Betty say she has a new boyfriend." 或 "I overheard Betty saying she has a new boyfriend." 也都可以。
這句話應屬於reported speech, 最後一句話的動詞應用過去式,若要更精準,I overheard Betty say she HAD a new boyfriend.
當一句話有兩動詞時,
第一動詞是真動詞, 第二動詞有可能是Ving, V-ed, 或原型V
quote沒錯喔
因為overhear的用法跟hear一樣
hear + n. + 原V / Ving