6.他是在我不知道的情况下私自拿走的。

7.必须警告吸烟者，医生已得出结论，吸烟会增加患肺癌的可能性。

8.他把自己的一生献给了儿童福利事业。

9.他在讲话中特别强调提高产品质量。

10.城市里有许多食品厂、服装厂和制造其他东西的工厂。

6.他是在我不知道的情况下私自拿走的。
It was taken away by himself alone without ever telling me.

7.必须警告吸烟者，医生已得出结论，吸烟会增加患肺癌的可能性。
Smokers should be warned that doctors have concluded smoking increases the chance of lung cancer.

8.他把自己的一生献给了儿童福利事业。
He devoted all his life to the cause of children's welfare.

9.他在讲话中特别强调提高产品质量。
He specifically stresses in his talk to improve the quality of the product.

10.城市里有许多食品厂、服装厂和制造其他东西的工厂。
The city has many food-procesing, clothes-making and other manufactories.