— Tom speaks Chinese very well. Who teaches him?— He studies by __________.
Which one do you think you’d like __________with you, Jack or Johnson?
The students were all tired, but ________of them stopped ____________ a rest.
Activities in our school __________ sports, language learning and music _________.
The poor little girl was _________young to know ______________ when her parents suddenly died in an accident.
They walked around the city to ____________ money for the children in disaster-hit areas after the terrible earthquake in Mexico.