Correct form of the verbs

When we arrived at the restaurant, the chef ______ (already/ prepare) our table.

By the time I got home, my roommate ____ (finish) all the pizza.

My grandma ____ (often/ cook) traditional meals from her home country.

If I ____ (know) how to make sushi, I would eat it every day.

Last summer, we _____ (visit) three countries in Europe.

If you ____ (not book) your flight soon, the price will go up.

Astronauts _____ (conduct) numerous experiments on the International Space Station since it was launched in 1998.

I ____ (study) English for five years and I still make mistakes.

A new satellite ______ (launch) by NASA last month.

If you ______ (practise) every day, you will get better at speaking English.