Choose the right option to complete the sentence. I ________ (call) you this morning, but you ________ (not / answer) the phone.

The correct answer is: called, didn't answer Explanation: The first blank requires a past tense form of "call". "Called" is the correct past tense form. The second blank requires the negative past tense form of "answer". "Didn't answer" is the correct form to express that the person didn't answer the phone. So the complete sentence is: I called you this morning, but you didn't answer the phone.