begin的過去式和過去分詞是什么？

　　We began work on the project in May.

　　我們于五月份啟動了這項工程。

　　He began by making a few general observations about the report.

　　開頭他先對這個報告作了幾點概括性的評論。

　　Slowly, an image began to appear on the screen.

　　屏幕上慢慢地出現了一幅圖像。

　　He took one smell of the liquid and his eyes began to water.

　　他聞了一下那種液體，就流起淚來了。

　　The music and wine began to make him feel sexy.

　　那音樂和酒逐漸使他性欲萌動。