He's not answering his cell phone. 他不接手機。
Will you please answer the phone? 你能幫我接個電話嗎?
Please answer the door. 幫忙開下門。
Could you answer it for me? (電話鈴響時)你能幫我接一下嗎?(門鈴響時)你能幫我開個門嗎?
Did you answer the phone? 你接電話沒?
I did, but they hung up as soon as I answered. 接了,不過我剛接起來,對方就掛電話了。