It's my daily routine to commute by tram.

The train fare is high, making my monthly expenses tough.

He is an expert in embryology, studying the developmental processes of many kinds of organisms.

The process of embryogenesis is very complex, with continuous cell division and differentiation.

The trolleybus is very convenient as a means of urban transportation.

He is writing a thesis on abiogenesis.

I am majoring in developmental biology at university.