单项选择题
A．He wants his students to be on time for class. B．He doesn’t allow his students to tell jokes in class. C．He is always punctual for his class. D．He rarely notices which students are late.
A．There were fatal mistakes in its design. B．The builder didn’t observe the building codes of the time. C．The traffic load went beyond its capacity. D．It was built according to less strict earthquake-resistance standards.
A．One of Etna’s recent eruptions made many people move away. B．Etna’s frequent eruptions have ruined most of the local farmland. C．Etna’s eruptions are frequent but usually mild. D．There are signs that Etna will erupt again in the near future.