1 were able
2 have to
3 should
4 May
5 must
длительная невесомость
математическое моделирование
new types of alloys
conduct numerous experiments
on Board of passenger ship
1 were able
2 have to
3 should
4 May
5 must
длительная невесомость
математическое моделирование
new types of alloys
conduct numerous experiments
on Board of passenger ship