What does "have sentences 100" mean?

This phrase is unclear, but it likely means:

1. "Write 100 sentences" (an exercise instruction)
2. "Has 100 sentences" (a document contains 100 sentences)
3. A grammatical error needing correction. If it's an assignment request, students should write 100 practice sentences demonstrating grammar rules, vocabulary, or sentence patterns. Context determines the exact meaning, but it most commonly refers to sentence-writing exercises.