"Why did you go to the cinema?"
"_________ there was a good film on."

"I didn't go to the cinema but there was a good film on." is another way of saying,
"_________ there was a good film on, I didn't go to the cinema."

"Why did you eat the chocolates?"
"_________ I like them."

"I like chocolates but I didn't eat the ones you left for me." is another way of saying,
"_________ I like chocolates, I didn't eat the ones you left for me."

"Why did you go to London?"
"_________ I wanted to see the Queen."

"I went to London but I didn't see the Queen." is another way of saying,
"_________ I went to London, I didn't see the Queen."

"Why are you learning English?"
"_________ I want to get a better job."

"I speak fluent English but I didn't get the job." is another way of saying,
"_________ I speak fluent English, I didn't get the job."

"Why are you walking in the woods?"
"_________ the weather is good and I need exercise."

"It was raining but I went for a run in the woods." is another way of saying,
"_________ it was raining, I went for a run in the woods."