begin的過去式和過去分詞形式是什么

　　例句：

　　Everyone began talking at once.

　　大家同時開始講話。

　　Academically he began to excel.

　　他開始在學術上脫穎而出。

　　He began to perspire heavily.

　　他開始大量出汗。

　　American forces have begun a big landing.

　　美軍已經開始大規模的登陸。

　　Rain had begun to streak the windowpanes.

　　雨已開始在窗玻璃上留下條痕。

　　Jesse has begun to outshine me in sports.

　　杰西開始在體育上使我相形見絀。