～合う
Do an action mutually with one another
You’ll be able to form verbs describing reciprocal actions shared between two or more people.
蓮と芽衣は手を取り合って、橋を渡りました。
ren to mei wa te o toriatte, hashi o watarimashita.
What do you think this sentence means?
Ren and Mei held hands and crossed the bridge together.
Perform an action reciprocally with each other
Attach 合う to the verb stem to express that two or more people perform the same action mutually or collaboratively ("...each other", "...together").
友達と写真を見せ合った。
tomodachi to shashin o miseatta.
My friend and I showed each other our photos.
姉と私は服を貸し合っている。
ane to watashi wa fuku o kashiatte iru.
My older sister and I lend each other clothes.
Attach 合う to the masu-stem
Drop ます from the polite form and attach 合う. The resulting compound verb conjugates as a godan verb: 話し合います, 話し合って, 話し合わない.
チームの全員で何度も話し合って、方針を決めた。
chiimu no zen'in de nando mo hanashiatte, houshin o kimeta.
After discussing thoroughly with everyone on the team many times, we decided on a direction.
助ける vs 助け合う
A plain verb says one person does the action to another. Adding 合う makes it go both ways: each person does it to the other.
助ける, help (one way)
兄が弟を助けた。
ani ga otouto o tasuketa.
The older brother helped the younger brother.
Only one person helps.
助け合う, help each other
兄と弟が助け合った。
ani to otouto ga tasukeatta.
The brothers helped each other.
Both help each other; と links the two people.
同じ病気の患者たちが、月に一度集まって、お互いに励まし合っている。
onaji byouki no kanjatachi ga, tsuki ni ichido atsumatte, otagai ni hagemashiatte iru.
Patients with the same illness get together once a month and encourage one another.
電車の座席は、みんなで譲り合って使いましょう。
densha no zaseki wa, minna de yuzuriatte tsukaimashou.
Let’s all give way to one another and share the seats on the train.
弟と私は、一つしかないケーキを半分ずつ分け合った。
otouto to watashi wa, hitotsu shika nai keeki o hanbun zutsu wakeatta.
My younger brother and I shared the only cake, half each.
7 more examples in the grammar path — free for a limited time.