for fear that lest in case 后面必须接虚拟语气吗

for fear that lest in case 后面必须接虚拟语气吗

不是的。
I will take an umbrella in case it rains.
亲：祝你学习进步，每天都开心V_V！
望采纳，thx!

虚拟语气用于名词性从句 （1）虚拟语气在宾语从句中的运用。 ①“wish + 宾语从句”表示不能实现的愿望，译为“要是……就好了”等。表示现在不能实现的愿望，从句中的谓语动词用一般过去时；表示将来不能实现的愿望，从句中的谓语动词用“would/could + 动词原形”；表示过去不能实现的愿望，从句中的谓语动词用“had + 过去分词”或“could(should) + have + 过去分词”。如： i wish it were spring all the year round. i wish i had known the answer. i wish i could fly like a bird. ②在表示建议、要求、命令等的动词suggest、advise、propose、demand、require、insist request、command、order等后的宾语从句中，谓语动词用should + 动词原形或是动词原形。如： she suggested we (should)leave here at once. the doctor ordered she should be operated. （2）虚拟语气在同位语从句和表语从句中的运用。 作表示建议、要求、命令等的名词advise、idea、order、demand、plan、proposal、suggestion、request等的表语从句和同位语从句，从句中的谓语动词用“（should） + 动词原形”。如： his suggestion that we (should)go to shanghai is wonderful. my idea is that they (should)pay 100 dollars. （3）虚拟语气在主语从句中的运用。 在主语从句中，谓语动词的虚拟语气用“should + 动词原形”的结构，表示惊奇、不相信、理应如此等。如： it is necessary(important, natural, strange, etc.)that we should clean the room every day. it was a pity (a shame, no wonder, etc.)that you should be so careless. it will be desired(suggested, decided, ordered, requested, proposed, etc.)that she should finish her homework this afternoon. 注意：这种从句表示的是事实。如果说人对这种事实表现出惊奇的情感，就可用虚拟语气。反之，如果不表示惊奇等情感，that从句也可用陈述句语气。如： it is pity that you can’t swim. 虚拟语气在其他场合的运用 （1）虚拟语气在as if/as though、even if/even though等引导的表语从句或状语从句中，如果从句表示的动作发生在过去，用过去完成时；指现在状况，则用一般过去时；指将来状况则用过去将来时。如： he did it as if he were an expert. even if she were here, she could not solve the problem. （2）虚拟语气用于定语从句中。 这种从句常用于句型“it is (high)time (that) … ”中，定语从句的谓语动词用一般过去时(be用were)或should + 动词原形，意思是“(现在)该……”。如： it’s time that i picked up my daughter. it’s high time we were going. （3）虚拟语气用在if only引导的感叹句中。如： if only i were a bird. if only i had taken his advice. （4）虚拟语气在一些简单句中的运用。 ①情态动词的过去式用于现在时态时，表示说话人谦虚、客气、有礼貌或语气委婉，常出现在日常会话中。如： it would be better for you not to stay up too late. would you be kind enough to close the door? ②用于一些习惯表达法中。如： would you like a cup of tea? i would rather not tell you.