Kuya can you hear me?

"Look what I made in school, kuya." Bela wanted to impress Gabi.

"Two cans and a string? What's that?" a bored Gabi replied.

"It's a telephone! Look, put this can on your ear and I will whisper on the other."

"I can't hear you. Sorry." Gabi said, obviously not wanting to play this game with his younger sister.

"Hmm..." Bela was puzzled since the device worked perfectly earlier in school. "Since I was using it earlier today, maybe now it's low batt?"