Sentence combing - pioneered by Kellogg W. Hunt and John Mellon, extended by Frank O'Hare and popularized by William Strong and William L. Stull.
Sentence combining is to help you strengthen their writing skills and practice the stylistic choices available.
Sentence combining practice, sentences contain (1) the increasing modification of nouns by large clusters of adjectives, relative clauses, and reduced relative clauses: (2) the increasing use of nominalizations other than nouns and pronouns for subjects and objects: (3) the embedding of sentences to an increasing depth. (Molfett 162-163).
Before: I went to the football game. I saw the cheerleaders. They are dressed in blue and white. I saw the coaches. They looked worried. This was a tough game. Mojo had a reputation. They always won.
After: At the football game I saw the cheerleaders dress in the school's colors-blue and white. The coaches looking worried, knew this would be a tough game against Mojo because of their reputation. They always won.
Activity: Divide the students into groups. Each group works with a series of clusters related to a single topic. For example Hamburgers. A scribe in each group writes out the suggested combinations, which the group later shares with the class or hands in to the teacher. Students in each group star the combination they thinks is best or most effective and present rationales for their decision. These collaborative sessions enhance learning, are less threatening than whole-class work, and are enjoyable. This strategy works equally with pairs of students or individual students.