It was very hot in the afternoon, and I was sleepy, but I managed to study a little. I’m happy. I think studying and writing make me happy but I’m lazy to do them because they require energy.

Finally I figured out that the two sentences are equivalent: 1) If a person gets infected, then D will get infected; 2) If any person gets infected, then D will get infected.

I felt fat even though I took a 30 minutes walk in the morning to the beach and back. And I have been doing sit-ups. I think I shouldn’t eat too much for dinner because my body does not need the calories.