(2013·江苏，33)With inspiration from other food cultures，American food culture can take a________for the better.

Last night, your mobile phone was always busy. I couldn’t ______ to you after several attempts. 

(2013·福建毕业班质量检查)—What does PM 2.5 mean?—It's a professional ________ indicating the condition of air pollution.

The ________ on driving after drinking alcohol is being carried out all over the country, which is helpful to reduce traffic accidents.

The questions the reporter asked sometimes were ________ and they made me ________.