集中

1. 请集中考虑以下问题。
   Please focus your minds on the following problem.
2. 我累了就无法集中精力工作。
   I can't concentrate on my work when I'm tired.
3. 吵闹声不绝于耳，我很难保持精神集中。
   I found it hard to keep my concentration with such a noise going on.
4. 紧张和疲劳常使人精神不集中。
   Stress and tiredness often result in a lack of concentration.
5. 他集中心思在新计划上。
   He focused his mind on his new plan.
6. 改用煤气集中供暖将节省大笔开支。
   Conversion to gas central heating will save you a lot of money.
7. 我试图使思想集中起来，但是我太激动了。
   I tried to collect my thoughts but I was too excited.

中的英语翻译：