We are learning English, but how can we learn English well ? A student can know a lot about English, but maybe he can't speak English.
If you want to know how to swim, you must get into the river. And if you want to be a football player, you must play football. So, you see, you can learn by using it. You must listen to your teacher in class. You must speak English to your classmates every day and also you must write something in English. Then one day you may find your English very good .

依次填入下列句子横线处的词语，最恰当的一项是（   ）。

①在这次国际会议上，我国政府再次郑重________：台湾是我国不可分割的领土，绝不容许任何人制造两个中国。

②中国常驻世界贸易组织代表团28日在日内瓦湖畔威尔逊总统酒店举行了________的揭牌开馆仪式。

③我国自己研制的无人飞船“神舟三号”发射成功，________着我国载人航天事业取得了重要进展。