If the researchers are successful, they an important step in reproducing the way that humans use cognition(认识力)to interact(交流;互动)in their world.
The boy always spent the whole day ______ in the room reading English during the holiday.
Bad habits, _______ formed, are difficult, and sometimes impossible to shake off.
The monument was built in honor of the explorer who was believed _____ the river.
________ blood if you can and many lives will be saved.
_______ the morning of my mother’s birthday, I usually help my mother do some housework.