单选题 The experts are introducing _________ to the farmers, which can increase the productivity.

单选题 Once it is given a correct program, a computer can operate _________ at a high speed.

单选题 _________ messaging is a form of real-time direct text-based communication between two or more people using personal computers.

单选题 The research team gave a(n) _________ assessment of the utility of nuclear weapons.

单选题 To ensure this, we pay close attention to quality and _________ programs.

单选题 I’ve had my eyes tested and the report says that my _________ is perfect.

单选题 Scientists have made a _________ in the treatment of that disease.

单选题 Passengers have to pay _________ charges for their extra baggage.