专四专八考试

【单选题】 A man escaped from the prison last night. It was a long time ______the guards discovered what had happened.
A．before
B．until
C．since
D．when

网考网参考答案：A
网考网解析：
“It's... before”句型表示“(……之后)才……”之意。until直到……为止．在否定句中多译为直到……才，该词一般不用在it is...until肯定)句型中。It is (has been)... since 句型表示自……以来已有……时间了。 查看试题解析出处>>