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I asked Beth to give Laura a quick call to ask her if she could come down right away . " She 's coming , " Beth said after the call . Two Chinese students , Toby and Leon ( their American names ) , who both looked about 19 years old , had arrived by now . I could tell that they were excited to accompany us to Dr. Zhang 's home , but they seemed nervous .
Why did the speaker think that the Asian students looked particularly young ?