Раскройте скобки и поставьте глагол в нужную форму Simple.

1. Our students (to specialize) in many fields of engineering.
2. At that time people (to develop) useful tools and devices.
3. Next year they (to study) new subjects.
4. Ancient Greeks (to construct) a lot of civilian structures.
5. This engineer (to work) in the field of mechanics.