用可能和是
In this sentence, 我认为我可能是需要一个医生, I use 可能 with 是 coming right after it. I've noticed that in some situations, 可能 does not need 是 to come after it (for example, 我想你可能太累). Is there a strict rule for when 是 does or doesn't come after 可能, or is this just another flexible part of the Mandarin dialect?