Oceanographic observations are very difficult, but they are fun.
Are you?  Do you?
 It's hard, so maybe it's fun.
ABC of oceanographic observations are considered.
A
 I don't say that I'm sleepy or tired.
B
 I don't brag about not sleeping.
C
 It's an endurance tournament without winners.
(Second, time is strict, which is too common, and "loose" doesn't get in.)
That is to say,
Recently, students have participated in the tournament, and I have come to enjoy watching the students grow around the side watching the tournament.
The haggard figure of Kijima no kimi (alumni), who looks like a bear, is impressive. He should be working hard at a private company right now.
(It may be said to be black ○△×.)