Wind power is an ancient source of energy ________ we may return in the near future.
The player kept on running ___ it was raining heavily.
---Hello.May I speak to Lucy? ---_____! Please…I’m afraid she is ____.
The light is out in her room. She ___ to bed.
---Excuse me, is this seat taken?---____.Please have a seat.
It was in the street __ this little girl saw a great scientist named Einstein for the first time in her life