— You should your teacher’s advice if you want to improve your science.— That sounds great.
They are _______ little sheep that we can’t make much money by selling _______.
---Do you know how long ________? ----I’m sorry I don’t know.
Jim has many hobbies, ________ swimming, hiking and playing badminton.
I _____ the book for two weeks. I must return it to the school library.
Though it was very late, they _______their discussion.