________ the second lap, Li Ping is ________ front.

1. A.
   On… in
2. B.
   On… at
3. C.
   At… on
4. D.
   At… in

________ the first lap, he was behind the others.But ________ the end of the third lap, he was first!

1. A.
   At, on
2. B.
   On, at
3. C.
   On, on
4. D.
   At, at

________ the second lap, Li Ping is ________ front.

[　　]

________ the second lap, Li Ping is ________ front.

[　　]

________ the first lap, he was behind the others.

But ________ the end of the third lap, he was first!

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