To his mind, the collaborative development of Beijing, Tianjin and Hebei province is to solve the problems _____ Beijing faces, such as overpopulation, traffic jams, and etc.
A.that | B.whether | C.when | D.why |
推荐套卷
To his mind, the collaborative development of Beijing, Tianjin and Hebei province is to solve the problems _____ Beijing faces, such as overpopulation, traffic jams, and etc.
A.that | B.whether | C.when | D.why |