我没有主意用英文怎么说

你可以说 "I don't have any ideas." 这是一个常用的表达方式，意思是你目前没有任何想法。

例如:

I've been trying to think of something, but I don't have any ideas.
(我一直在试着想想，但是我没有任何主意)
Can you help me out? I don't have any ideas for dinner tonight.
(你能帮帮我吗？今晚晚餐我没有任何主意)