He's tired and can't concentrate.

英 美
  • and conj.和;加;接着;那么
  • cant n.倾斜;斜面;斜角;伪善之言;黑话v.(使)倾斜;伪善地说;说术语adj.倾斜的
  • concentrate v.专心;集中;浓缩n.浓缩物
  • HES abbr.厚漆单层丝色的(=Heavy-EnamelSingle-Silk)
  • tired adj.疲倦的;疲劳的;累的;厌烦的动词tire的过去式和过去分词形式.