# data[].attributes.headline
it depends on each situations. In the first 2 videos, it would be inappropriate, if they talk about their personal life. But it's fine for video 3. 

# data[].attributes.subject
it depends on each situations. In the first 2 videos, it would be inappropriate, if they talk about their personal life. But it's fine for video 3. 

# data[].attributes.headline
comparing, expanding a topic, narrowing a topic, connecting

# data[].attributes.subject
comparing, expanding a topic, narrowing a topic, connecting