happen有进行时态和被动语态形式吗？

happen有进行时态但是不可用于被动语态。
例如：It is happening as we speak.（现在进行时）

happen 英[ˈhæpən] 美[ˈhæpən]
vi. 发生; 出现; 碰巧; 偶然遇到;
[例句]
1、We cannot say for sure what will happen.
我们无法确定会发生什么事。
2、She wondered what would happen if her parents found her.
她不知道如果父母找到自己会有什么结果。
3、If we had been spotted at that point, I don't know what would have happened to us.

如果当时我们被发现了，我不知道会有什么后果。
4、We happened to discover we had a friend in common.

我们凑巧发现我们有一个共同的朋友。
5、She called Amy to see if she had any idea of her son's whereabouts. As it happened, Amy had.

她打电话给埃米，看她是否知道自己儿子的行踪。埃米还真就知道。

有进行时，没有被动语态