Correct the wrong usage of words to do with written work in these sentences.

1. His PhD assignment was 90,000 words long and was on the history of US place names.
    
2. Little Martha did her first dissertation in school today. It was called ‘My family’.
    
3. We have to hand in an essay at the end of the course. It can consist of up to five different pieces of work.
    
4. The teacher gave us the title of this week’s project today. We have to write 1,000 words on the topic of ‘If I ruled the world’ and hand it in next Monday.
    
5. At the end of this course, you have to do a 5,000-word thesis which will be assessed, and the grade will contribute to your final degree.
    
6. I think I’ll do a study of people’s personal banking habits for my MSc composition. It has to be about 12,000 words.
    
7. I’ve chosen to do the portfolio instead of the two exams, because I like to do one single piece of work where I can research something that interests me personally.