手を挙げる

てをあげるteoageru

expression · ichidan verb

1. to raise one's hand
2. to surrender
3. to raise one's hand to someone (as a threat to strike)
4. to become better (at something)
5. to improve
6. to throw one's hat in the ring
7. to volunteer
8. to indicate one intends to participate

Study it in Yanamino