1. 对......开放：be similar to 和......相似 | be open to 对......开放 | be loyal to 对......忠诚

2. 向---开放：53.say good-bye to sb向某人道别; | 54.be open to 向---开放; | 55.ring sb back给某人回电话;

3. 向......开放;通往：be of much/no value to 对......有/没有价值 | be open to 向......开放;通往 | be out of control失控;不能被控制住

4. 对......开放,易受到：be important to 对......重要 | be open to 对......开放,易受到 | be opposed to 反对,不赞成