1、Install a burglar alarm if you can afford it as another line of defence against intruders.
如果你能負(fù)擔(dān)的話，安裝一個(gè)防盜報(bào)警器作為對(duì)入侵者的另一層防御。

2、Residents have the responsibility of being the first line of defence against wildfires.
居民有責(zé)任成為野火的首要防衛(wèi)人員。

3、Password is the first line of defence of network system.
口令是網(wǎng)絡(luò)系統(tǒng)的第一道防線。