没有完整的句子,很难判断需不需要加定冠词.例如以下两个句子都选自英国BBC网站,都是materials作主语,一句有定冠词,另一句则没有
The materials will be designed at NQF levels Entry 3,Level 1 and Level 2 and will...
（见www.bbc.co.uk/radio3/worldmusic/a4wm2007/education.shtml ）
Materials that breathe and materials that change colour and so on as technology moves on.
（见www.bbc.co.uk/cbbc/find/?q=materials&start=40&scope=cbbcsearch&link=prev ）