| Comments on Approach 1-Processing instruction | Sum | Percentage |
| Using a variety of teaching approaches | 7 | 13.73% |
| Focusing on forms | 7 | 13.73% |
| Using when students’ level allows | 3 | 5.88% |
| Not fitting students’ ability | 2 | 3.92% |
| Interesting | 2 | 3.92% |
| Boring | 2 | 3.92% |
| Using when time allows | 1 | 1.96% |
| Using when materials are provided | 1 | 1.96% |
| Using video clips | 1 | 1.96% |
| Useful | 1 | 1.96% |
| Not identifying the use and the reason of the usage of -ed | 1 | 1.96% |
| Effective | 1 | 1.96% |
| Arousing students’ awareness | 1 | 1.96% |
| Comments on Approach 2-Mechanical drill | Sum | Percentage |
| Using a variety of teaching approaches | 5 | 9.80% |
| Focusing on forms | 5 | 9.80% |
| Using when students’ level allows | 3 | 5.88% |
| Boring | 2 | 3.92% |
| Using when time allows | 1 | 1.96% |
| Using video clips | 1 | 1.96% |
| Interesting | 1 | 1.96% |
| Not fitting students’ ability | 1 | 1.96% |
| Easy to check answer | 1 | 1.96% |
| Comments on Approach 3-Meaningful drill | Sum | Percentage |
| Using a variety of teaching approaches | 5 | 9.80% |
| Using when students’ level allows | 3 | 5.88% |
| Focusing on forms | 2 | 3.92% |
| Using when time allows | 1 | 1.96% |
| Using video clips | 1 | 1.96% |
| Interesting | 1 | 1.96% |
| Easy to check answer | 1 | 1.96% |
| Comments on Approach 4-Communicative drill | Sum | Percentage |
| Using a variety of teaching approaches | 5 | 9.80% |
| Using when students’ level allows | 4 | 7.84% |
| Focusing on forms | 2 | 3.92% |