1、broadcast

broadcast vt.;vi.广播;播放。已往式和过去分词均为broadcast。

①the bbc broadcasts every day.bbc天天都广播。

②the news was broadcast on the radio.这个音信是收音机里播送的。

2、but

but prep. 除…之外。与except同义，除了的部分与其他部分不在一个范围内，不具有一致性。except合用场合较多，but 主要用于带有nothing/nobody/no one/all 等不定代词的句子。

①No one except/but you was late.除你之外没有迟到。（你迟到了）

②We all went to see a film yesterday evening except/but you.除你之外作天晚上我们都去看电影了。（你没去）

③That window is open except in winter .除冬天外那窗户一直开着。（冬天不开）

另外，but后可接不不定式。如果句子前面有实义动词do及其变化形式时，不定式不带to; 否则不定式带to .

①I did nothing yesterday evening but watch TV.昨天晚上除看电视外我什么也没干。

②He had no choice but to leave.他只得离开。

注意：besides 也是介词，意为“除……之外（还有）”。除了的部分和其他部分在同一个范围内，具有一致性。

①We all went to see a film yesterday evening besides you.除你之外昨天晚上我们也都去看电影了。（你和我们都去了）

②Who is going there with Tom besides you? 除你之外还有谁和汤姆一起去？

3、but for

该短语介词意为“要不是……”，后接名词（=without + n.）,but for…短语相当于一个虚拟条件句，因此，句中谓语动词用虚拟语气。如：

The boy would have drowned but for your help.

如果接的是句子，but for要换用成but that…如：

He would have helped us but that he was short of money at the time.(= if it had not been the fact that he was…)