4 sentences

1. 全军进入了戒备状态。

   quán​jūn jìn​rù le jiè​bèi zhuàng​tài.

   The entire army has gone on high alert.

   Source: Dong Chinese Dictionary

2. 我们处于高度戒备状态，我得走了。

   wǒ​men chǔ​yú gāo​dù jiè​bèi zhuàng​tài, wǒ děi zǒu le.

   We are on high alert and I have to go.

   Source: OpenSubtitles

3. 由于局势紧张，边防部队加强了戒备。

   yóu​yú jú​shì jǐn​zhāng, biān​fáng bù​duì jiā​qiáng le jiè​bèi.

   Due to the tense situation, border troops have increased their vigilance.

   Source: Dong Chinese Dictionary

4. 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