下列事件为必然事件的是（　　）

    Next, he ____ (put, putted) two pots ____ (in, into) two big bowls and filled ____ (both, all) pots ____ (by, with) water. He put the gold into one pot, and some water ____ (ran, run) into the bowl. Then he put the crown into____ (other, the other) pot. This time, ____ (even, ever) ____ (more, less) water ran into the bowl.

近年来，我国对稀土资源的整合可谓“步步为营”，国际上要求我国扩大出口之声不绝于耳。面对国际压力，商务部表态，我国将继续对稀土的开采、生产和出口的各个环节实施限制措施。这给我们实行对外开放的启示是（  ）

①要限制出口，扩大进口              ②要维护国家的经济安全　

③要注重对国际贸易规则的充分利用　  ④必须坚持独立自主、自力更生