1. 说实话，我对汤姆的学业有几分担心。
    ______ ______ ______, I am ______ of worried about Tom's schoolwork.
2. 如果不是水尽粮绝，我们将不会停止宿营。
    We won't stop camping ______ we ______ ______ ______ food and water.
3. 你应当把钥匙藏在除了我俩谁也找不到的地方。
    You should ______ the keys ______ ______ ______ us two.
4. 工人们靠自己的力量最终生产出了这种主要针对国外市场的新型玩具。
    The workers ______ ______ themselves and finally produced the new type 
    of toys which mainly ______ ______ the foreign markets.
5. 即使有许多人不同意，他也会坚持自己的想法。 
    ______ ______ many people don't agree with him, he will still ______ ______ 
    to his own idea.