3 sentences

1. 该组织的首脑最近在电视上发表了演说。

   gāi zǔ​zhī de shǒu​nǎo zuì​jìn zài diàn​shì shàng fā​biǎo le yǎn​shuō.

   The head of the organization recently gave a speech on television.

   Source: Dong Chinese Dictionary

2. 由于有重要首脑出席，会场的戒备非常森严。

   yóu​yú yǒu zhòng​yào shǒu​nǎo chū​xí, huì​chǎng de jiè​bèi fēi​cháng sēn​yán.

   Due to the presence of important leaders, security at the venue is very tight.

   Source: Dong Chinese Dictionary

3. 双方一致同意推迟原定于下月举行的首脑会议。

   shuāng​fāng yī​zhì tóng​yì tuī​chí yuán dìng yú xià yuè jǔ​xíng de shǒu​nǎo huì​yì.

   Both sides agreed to postpone the summit originally scheduled for next month.

   Source: Dong Chinese Dictionary