— Jack always comes first in the exams, but he never . — What a modest student!
—Did you see him yesterday? —No, when I got to the airport, he a taxi for home.
The old scientist devoted most of his time ___________ the space science.
_________good advice! It’s so helpful to us.
—Mary was heard_______ just now. What happened? —John was telling a joke.
Even if we are very busy, we should spend ______ doing exercise every day.