1950s in the USA, most families had just one phone at home, and wireless phones _______ yet.

r their common interests, they_____cooperated so smoothly in the investigation of the case

learn to live in the present, ________ think somuch about the future or the past

Peking Opera is widely regarded as a symbol of Chinese culture, it has been losing young audiences due to its __________ outdated style and slow rhythm.

He is badly ill. He eats _____.