鳃丝上的横纹肌有节律的收缩可以起到“鳃心”的作用。
查看答案
每个鳃弓上分布有两列鳃瓣,每列鳃瓣称半鳃。
A. 对
B. 错
According to the news, which of the following is true?[音频]
A. The month ofJanuary in Japan logged a record trade deficit.
B. The highest deficit in Japan is in 1979.
C. The highest deficit in Japan is in the 2008financial crisis.
D. The deficit in 1979 was 18.6 billion US dollars.
Whose investment was going to overseas?[音频]
A. Only foreign investment.
B. Foreign investment, foreign companies,international companies and Japanese corporations
C. Only international companies
D. The foreign companies and internationalcompanies.
According to the news, what is true about tax?[音频]
A. There are various kinds of tax.
B. They’reall fees that governments collect in order to pay for the food.
C. Theycan be used to pay for services that people provide.
D. Theycan be used to pay for goods that companies provide.
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