Low-carbon lifestyle is of great benefit to improve the world environment.________can be enjoyed from it until you have a deep understanding of it, however.
— Hi, Tracy, you look tired. I am tired. I_______ the living- room all day.
— Did Mike call ______you yesterday? — No, but this morning he called _______my office.
It is such a modem machine ____few of the workers know how to operate it.
_____ in bed, we listened to the heavy rain _______ the window.
Is_____ necessary ____them to stop ________ every two hours?