Learn Arabic (Modern Standard): سمعنا إنذار الحريق في منتصف الليل. - We heard the fire alarm in the middle of the night.

إنذار الحريق is an Idafa (a possessive or 'of' phrase), literally meaning 'the warning of the fire.' In this structure, the first word never takes الـ (the) but is automatically considered definite because the second word (الحريق) has it.

What is the root of إنذار and how does it relate to its meaning?

The word إنذار means 'warning' or 'alarm.' It is the verbal noun (masdar) of the verb أنذر (to warn), which comes from the root ن ذ ر, a root related to vowing, dedicating, or warning.

How do you say 'midnight' in Arabic based on this sentence?

Arabic typically doesn't use a single compound word for midnight. Instead, it uses the phrase منتصف الليل, which literally translates to 'the middle of the night.' The word منتصف (middle/midpoint) comes from the root ن ص ف, which gives us words related to halves, like نصف (half).

Does the ـنا suffix in سمعنا mean 'we' or 'us'?

Here, it means 'we' (سمعْنا = we heard). When the ـنا suffix is attached to a past tense verb where the final root letter has no vowel (a sukoon), it acts as the subject 'we'. If the final root letter had a short vowel (like سمعَنا - he heard us), it would be the object 'us'.