Senior 3 high school students should be given enough sleeping time, ____________ they are busy preparing for exams to enter college.
After we walked ______ the forest, and ______ a river, we arrived at that small village.
We were about to leave the classroom _____ it began to rain.
Three students in ten will go and _____ to stay in the classroom.
The beef is too expensive. I won’t buy it _____.
The medicine _____ natural plants.