1. Because of the students' laziness and untidiness, the teacher was angry with them.
2. Because of no available bench in the school garden, we have nowhere to sit and rest.
3. Because some students are afraid of making mistakes, they don't want to answer the questions during class.
4. Because I had a terrible flu, I couldn't go to school two days ago.
5. Because Mr. Thomas needs to prepare some question for the exam, he won't be able to sleep well tonight.
6. Because it was warm and sunny, the Robinsons decided to go for a picnic.
7. Because the ground was wet and muddy, the football players had difficulty playing the match.