自2010年至今的四级考试中， 共出现过 次
自2010年至今的六级考试中， 共出现过 次
Had is the past tense and past participle of have .
AUX （had 有时代替 if 用于从句句首，表示某种情况可能发生但并未发生） Had is sometimes used instead of 'if' to begin a clause which refers to a situation that might have happened but did not. For example, the clause 'had he been elected' means the same as 'if he had been elected'.
Had he succeeded, he would have acquired a monopoly...
Had I known what the problem was, we could have addressed it.
PHRASE 上当受骗 If you have been had, someone has tricked you, for example by selling you something at too high a price.
If your customer thinks he's been had, you have to make him happy.
PHRASE 遇到大麻烦;无望成功 If you say that someone has had it, you mean they are in very serious trouble or have no hope of succeeding.
Unless she loses some weight, she's had it...
He wants actors who can speak Welsh. Obviously I've had it.
PHRASE 受够了;忍受不了 If you say that you have had it, you mean that you are very tired of something or very annoyed about it, and do not want to continue doing it or it to continue happening.
I've had it. Let's call it a day...
I've had it with that kind of treatment of Americans.