1. — 你曾去過大連嗎?
    — Have you ______ ______ to Dalian?
    — 是的,去過.那是一個美麗的城市.
    — Yes, I ______. It's a beautiful city.
2. 我看過很多次英文電影了.
    I ______ ______ English films many times. 
3. 你曾聽說過外星人嗎?
    ______ you ______ ______ ______ the aliens?
4. 水族館里有如此多的不同種類的魚.
    There are ______ ______ different kinds of fishes in the aquarium.
5. 他們兩人都不擅長運動.
    ______ ______ them is good at sports.