a bad patch的用法和样例：
- My business has been through a bad patch recently and I have been unable to maintain a reasonable profit margin.
- Our firm has just struck a bad patch.
- She's been through a bad patch (ie a difficult or an unhappy time) recently.
- Their marriage has been going through a bad patch.
- strike a bad patch 倒霉(遭受不幸)...
a bad patch的相关资料：