He studies hard every day.

When a baby starts weaning, you begin to give them solid food little by little.

The baby has started to wean.

Day after day, he continued to strive to solve the problem.

She gave him a kiss.

He kissed her.

The mouse squeaked 'chu'.

I think that person is what you call a 'chuunibyou'.

I started studying for the junior high school entrance exam for junior high school students.

He received a command from his boss and started a new project.