Group 1 causative (う-verbs): Change u → a + せる

📝 Quick Summary

The Causative Form (使役形 – しえきけい) expresses making someone do an action (compulsion) or letting someone do an action (permission). For Group 1 verbs (う-verbs), change the final -u vowel of the dictionary form to its corresponding -a vowel and attach せる (seru).

Structure: [Group 1 Verb Dict Form (change final -u to -a)] + せる / せます
Example 1: せんせいは がくせいに ほんを よませます (The teacher makes/lets the students read books).
Example 2: おまたせして すみません (I am sorry for making you wait [lit. making you wait]).

💡 Raya’s Hack

The Standalone -う ➡️ -わせる Exception!
Just like with the negative 〜ない form, Group 1 verbs ending in a standalone う (u) change to わ (wa) before adding せる (seru):

– かう (kau) ➡️ かわせる (kawa-seru: to make/let buy)
– あう (au) ➡️ あわせる (awa-seru: to make/let meet)
– いう (iu) ➡️ いわせる (iwa-seru: to make/let speak)

Note that once converted into causative form (*-seru*), all causative verbs conjugate like standard Group 2 (る-verbs)!

🚧 Joy’s Mistake

🔥 Layer C: Retrieval Practice Loop

Retrieve and apply! Express causative action with Group 1 verbs. (Hiragana and English only)

Level 1: Structure Building (Group 1 Dict Form ➡️ Causative Form)

Level 2: Full Sentences