第33题: [单项选择]Britain might still be part of France if it weren't ______ a disastrous flood 200000 years ago, according to scientists from Imperial College in London. A. upon B. with C. in D. for 参考答案:D 答案解析:本题考点为介词的上下文语义。短语if it weren't for常用于虚拟语气,意为“要不是……的话”,其他选项都不能够形成通顺的上下文搭配。根据题意,选项D为正确答案。