My biological clock is disrupted, and I've been having sleepless nights.

He is receiving a basic living stipend.

He makes a living as a freelance designer.

He claims to be a 'breast alien' (slang for a person who is obsessed with breasts).

We are considering introducing a new production line.

He is an expert in orthoepy, teaching pronunciation.

He is an expert in planetary science.

Geopolitics is the key to understanding important aspects of international relations.

Let's try to predict tomorrow's weather using the future tense.

The present tense is used to express things that are happening now or general facts.