✍️ Writing: Punctuation & Capitalization
1ère Bac Sciences et Technologies Mécaniques STM
📌 Introduction
Correct punctuation and capitalization make your writing clear, professional, and easy to understand — especially in science reports and exams.
Science Tip: “In lab reports, every sentence must start with a capital letter and end with proper punctuation. Mistakes can cost points!”
🔤 Capitalization Rules
When to Use Capital Letters
- First word of a sentence: “The experiment began at 9 AM.”
- Proper nouns: “Dr. Ahmed”, “Atlas Mountains”, “Nile River”
- Days, months, holidays: “We did the test on Monday in March.”
- Scientific names: “Escherichia coli is a bacterium.”
- Acronyms: “DNA”, “RNA”, “ATP”
wrong: “the results showed bacteria in the water.”
correct: “The results showed bacteria in the water.”
🔚 Punctuation Rules
Key Punctuation Rules
- Period (.): Ends declarative sentences. “The plant grew quickly.”
- Comma (,): Separates items in a list. “We used water, soil, light, and temperature.”
- Question mark (?): Ends questions. “What were the results?”
- Exclamation (!): Rare in science (only for emphasis).
- Quotation marks (“”): For direct speech or quotes. “The teacher said, ‘Record your data carefully.'”
- Apostrophe (‘): For possession. “The student’s notebook was neat.”
Example: “We observed the cells. They were moving. What caused this? The student’s hypothesis was correct.”
✅ Exercise 1: Fix the Capitalization
Correct the capitalization in this paragraph:
the experiment began on monday. dr. el amrani presented the results. we studied escherichia coli in the lab. dna was extracted from the sample.
✅ Exercise 2: Add Punctuation
Add periods, commas, and question marks where needed:
what did you observe in the microscope the cells were moving quickly we used water light and nutrients the results were surprising
✍️ Writing Practice
Write 3 sentences about a science experiment. Use:
📌 Summary
- Always capitalize the first word of a sentence and proper nouns.
- Use periods to end statements, question marks for questions.
- Use commas in lists and to separate ideas.
- Double-check your work — small errors reduce clarity and marks!
