- Task Achievement
- Band 4.5
- Coherence and Cohesion
- Band 5.5
- Lexical Resource
- Band 6.0
- Grammatical Range and Accuracy
- Band 5.5
The given picture illustrates how a central heating system operates in a typical house in order to keep internal climate and tap water at a pre-set temperature. The process runs through two stages, starting at a transitory state until reaching a steady state.