maintain vt.保持,维持;保养,维护;抚养,赡养
maintain sth = cause sth to continue; keep sth in existence at the same level
英语解释如上。
maintain friendly relations 保持友好关系
preserve keep sth in an unchanged or perfect condition preserve one's eyesight保护视力汉语意思如下:
vt.保护;保持,保存;腌制食物;防腐处理
vi.保鲜;保持原状;做蜜饯;禁猎
we need to preserve the forest.
楼主,希望对你有帮助。