本题重点考查介词的用法。从全句来看，主句使用了虚拟语气，因此主句前面部 分应该是表示非真实条件的，而except不能引导非真实条件句，也不能放在介词词组中 来表示非真实条件。四个选项中只有B选项和D选项能够表示非真实条件，但是if only 引导的非真实条件句是表达强烈的遗憾，意为 “若是……该多好” ， but for是介词词 组，表 达 “要不是，如果没有” ，符合语义，故选B。
[参考译文]要不是在本季早期摔断了腿，他昨天就可以参加英格兰队对波兰队的比赛。
[语法拓展] 含蓄虚拟条件句的七种表现形式：英语中某些假设的条件句不是通过if从句表达出来， 而是通过某些短语、上下文或其他方式表达出来，其谓语也常用虚拟语气，这就是含蓄条件句。
①将条件隐含在不定式短语中。
e.g. I should be happy to go with you. (=I should be happy if I could go with you.)如果能与你一起去，我将很高兴。
To have studied harder, you would have passed the examination. (=If you have studied harder, you would have passed the examination.)如果你学习更用功些，你早就考及格了。
② 将条件隐含在分词短语中。
Bom in better times, he would have been a scholar. (=If he had been bom in better times, he would have been a scholar.)如果出生在好时代，他早就成为学者了。
Failing this time, what would you do? (=If you failed this time， what would you do? ) 假若 这次失败，那你怎么办？
Walking alone in the dark, Mary would be terrified. (=If Mary walked alone in the dark, she would be terrified.)要是一个人单独在黑暗中走，玛丽会感到十分害怕。
③ 将条件隐含在介词短语中。
e.g. Without air， no one could live. (=If there were no air， no one could live.)没有空气，人就不能活。
But for our help, he would have failed. (=If it hadn5t been for our help, he would have failed.) 要不是有我们的帮助，他就会失败。
④ 将条件隐含在名词短语中。
e.g. A few hours earlier, and you would have seen the famous writer. (=If you had come a few hours earlier， you would have seen the famous writer.)要是你早来几个小时，你就见到这 位著名的作家了。
⑤ 将条件隐含在某些连词中。
e.g. I didn't know that he was a cheat, or else I wouldn't have believed him. (or else=if I had known he was a cheat)我不知道他是个骗争，不然我也不会相信他了。
I'm really very busy, otherwise I would certainly go there with you. (otherwise=if I were not so busy)我真的是太忙了，不然我就会同你一道去了。
⑥ 将条件隐含在定语从句中。
e.g. Anyone who had seen that painting might have taken it for a photo. (=If anyone had seen that painting， he might have taken it for a photo.)凡是看过那张画的人，都可能把它看成 是照片。
⑦ 将条件隐含在一定的上下文中。
e.g. Don't bother to read all these papers. It would take too long. (=If you read all these papers, it would take too long.)不要费事看所有这些文件了，那会花太多时间。