fell的过去式是什么？

fellvt. 砍伐；打倒；击倒

fell的过去式和过去分词是felled。

例句：

Badly infected trees should be felled and burned.

严重感染的树木应该被砍掉并焚烧。

But other students often felled him at the fence class for fun. 跟读

但其他学生常常在击剑课上把他砍倒来取乐。