Defective verbs in the past tense (نسي)

Defective Verbs in the Past Tense

Verbs that end in a weak letter, such as alif maqsura (ى) or yaa (ي), are known as defective verbs (الناقص). Because these final letters are weak, they sometimes change or disappear depending on who is doing the action. Let's see how these behave in the past tense when talking about losing, finding, and remembering things.

Conjugating for "I", "We", and "You"

When conjugating for "I" (أنا), "we" (نحن), or "you" (أنت), the weak letter is written as a regular ي. If the base verb already ends in a ي, like نسي (he forgot), it simply keeps it. If the base verb ends in ى, like أخفى (he hid) or حكى (he told), the ى turns into a ي before the pronoun suffix is added.

Conjugating for "She"

When conjugating for "she" (هي), verbs that originally end in ى drop their weak letter completely before adding the feminine suffix ت. For example, أتى (he came) becomes أتت (she came), and أعطى (he gave) becomes أعطت (she gave).

However, verbs that originally end in ي, like لقي (he found) or نسي (he forgot), keep their weak letter before adding the ت. Without vowel marks, "I found" and "she found" look identical in writing (لقيت), though they are pronounced differently.

Conjugating for "They"

When conjugating for the plural "they" (هم), the weak letter drops completely for all defective verbs before adding the plural suffix وا. For example, مشى (he walked) becomes مشوا (they walked).

Here is another example showing the plural form of أخفى (he hid) dropping its weak letter.

Summary of Defective Past Tense Endings

Here is a quick overview of how these verbs change, using حكى (to tell) and نسي (to forget) as examples:

Let's see these rules applied together in one final example.