--What are the tractors used for?

--The tractors are used for ______.

--Which subject do you like best?

--P. E. P. E. ______ by everyone in our class.

--I'm flying to Hainan Island for my holiday this weekend.

--Wonderful! ______

--Hello, where are you going?

--Oh, I ______ for Hong Kong.

---________ he like dolphins?

---Because they are very intelligent．

---I’m ________ Helen.

---Have you seen her?

---Have you finished your homework?

---No, I haven't. But I ______ it tomorrow.

---Have you ever visited any wonders of Beijing?

---Yes, I ______. I ______ them last summer holidays.