That is my personal issue.

We are going on a trip together.

I lost my precious belongings.

He is majoring in entomology at university.

My grandfather is a famous entomologist.

I like collecting insects.

He is an expert in entomology, especially knowledgeable about butterflies.

His hobby is collecting insects.

Insects are an important part of the natural world.

There are people who are not good with insects.