She'll do it when he comes home. & She'll have done it when he comes home. What is the difference?

Do you think it is suitable for greeting to just say “Hi”?

We got vaccinated ourselves against hepatitis. We got ourselves vaccinated against hepatitis. What is the difference?

‎What is the difference between 에 의해서 и (으)로써? Please provide examples.

Is this sentence correct? Thank you to Miss Ji and the children for the wonderful class.

Thank you to Miss Ji and the children for the wonderful lesson.

Is this sentence correct? We have a music room on the second floor.

Hello, how are you, I am Julissa, Peruvian, who lives in Hollywood, Florida, and I would love to talk to people to practice my English. Although I live in the USA, my level is basic.