A:about to
B:starting to
C:beginning to
D:to
①宣布了和平统一的方针
②提出了海峡两岸实行“三通”的建议
③阐明了统一后对台基本政策
④建议两岸通航、通商、通邮和探亲旅游
The book was written in ______easy English ______even primary school students could understand it.