______ riding shared bikes（共享单车）is an environmentally friendly way to travel，many of the bikes are thrown everywhere.

Studying abroad, the boy was exposed to a way of life_________he was not at all fanmiliar.

I want to work for ____________ when I’m older.

________more about Chinese culture, Jack has decided to take Chinese folk music as his second course.

I don’t know if it ____ tomorrow. If it _____, we will go out for a picnic.