شرکت در آزمون آنلاین زبان انگلیسی 2 - زبان انگلیسی 2 | آزمون شماره 6749

.As soon as the shopkeeper understood that we weren't going to buy anything, his ..................................... changed

Thanks to vaccines, these diseases have been mostly eradicated in industrialized nations. The recent research shows that these vaccines may protect us against new diseases as they are produced to … .

Which sentence is grammatically CORRECT?

You can … a lot of experience and knowledge by doing volunteer work at the office.