Put the verbs in the brackets into the present continuous or the present simple

II. Put the verbs in the brackets into the present continuous or the present simple.

1.The Sun __________ (be) the main source of energy on Earth.

2.How many types of energy __________ (humans, use) at present?

3.My father __________ (replace) the old bulbs in my room at the moment.

4.It __________ (take) billions of lifetimes for new fossil fuels to form.

5.At the current time, many families __________ (look) for ways to use less energy.

6.We __________ (discuss) about the advantages of some energy sources now.

7.Today, governments __________ (face) multiple challenges of energy security.

8. __________ (you, visit) the biggest hydropower dam in the country at the moment?

9. Nowadays, critical changes __________ (take) place in the global energy system.

10.We'll choose electric vehicles if they __________ (be) more convenient and cheaper.