Flu is an ___ that attacks the respiratory system.
举一反三
- Closed-loop control system is an automatic control system. Open-loop control system is not an automatic control system.
- Which of the following is not the basic system of language?? The grammar system.|The word system.|The sound system.|Alphabet system.
- A computer system consists of hardware system and software system.
- The traditional Chinese system is a combination of the solar system and the lunar system.
- _____________ is the first organ of the respiratory system. A: Mouth B: Thorat C: Nose D: Pharynx