1. **Stating the problem:** We want to learn how to add a one-digit number to a two-digit number. 2. **Example:** Suppose we add $7$ (one-digit) to $34$ (two-digit). 3. **Step 1: Break down the two-digit number:** $34$ means $30 + 4$. 4. **Step 2: Add the units digit:** Add the one-digit number to the units digit of the two-digit number. $4 + 7 = 11$. 5. **Step 3: Handle carrying over:** Since $11$ is more than $9$, we write $1$ in the units place and carry over $1$ to the tens place. 6. **Step 4: Add the carried over 1 to the tens digit:** $30 + 10 = 40$. 7. **Step 5: Combine the results:** $40 + 1 = 41$. 8. **Final answer:** $34 + 7 = 41$. This method helps learners understand place values and carrying over in addition by breaking it into simpler steps.