Question

i was waiting for her but she didn't come the detective told his client

Answer 1

Answer:

In theory, both of these sentences are correct. In practice, no native English speaker would use the first construction. This is purely a matter of idiomatic usage.

Oddly, the first type of construction is frequently used in a negative sense, but hardly ever in a positive sense. In the famous Woody Guthrie song, “Worried Man Blues,” the last line of the chorus is:

“I’m worried now, but I won’t be worried long.”

Expressing the opposite sentiment would be:

“I’m not worried now, but in the future I’ll be worried for a long time.”

Answer 2

Answer:

that he had been waiting for her but she didn’t come.