| highly | 19 | degree |
| much more | 12 | degree |
| as an internal combustion engine | 8 | manner |
| fuel cell → be → efficient | 58 |
| fuel cell → be → more efficient | 22 |
| fuel cell → be → more efficient than combustion engines | 4 |
| fuel cell → be → more than efficient | 3 |
| fuel cell → become → more efficient | 3 |
| negative | neutral | positive |
| 0.038 | 0.242 | 0.720 |
| Raw frequency | 90 |
| Normalized frequency | 0.683 |
| Modifier score | 0.500 |
| Perplexity | 123.696 |