ملخص الدرس / الثآنية ثانوي/اللغة الإنجليزية/Grammar/could-managed to

the example:

Arab-Islamic scholars were able/ managed to establish longitudes and reform the calendar.

Europe was able / managed to develop because the Arabs brought with them the seeds of a new enthusiasm for science.

For expressing ability  in a particular situation, we use :

was/were able to + stem or managed to + stem