Parents and teachers should help teenagers control their use of computer games ______be controlled by themselves.
The US federal government has released 252 applications so far, ______ fields including education and health care.
This is a kind of effective classroom teaching ______ students learn independently and cooperatively.
The lecture was so complex that I simply couldn’t ______ at all. Could you explain it to me?
The show opens next Monday. Between now and then we ______ it in the school hall every day.
He likes to make a list of ______ she wants to buy before shopping.