It too sounds a fine idea, but even top private schools, with lots of money and good teachers, find it tricky to timetable lots of variation within one age-group's lessons.
3
但总的来说,他们是在勉为其难,因为工程师和设备的短缺,以及开采成本的增大。
But on the whole, they are struggling to increase their output, owing to shortages of engineers and equipment, and to the concomitant rise in development costs.