Put the words in brackets in the plurar. 1. (Business person)

Put the words in brackets in the plurar.
1. (Business person) are involved in the management of (company)
2.My father builds(bridge)
3.Every year they spend a couple of (month) at the seaside
4.In our orchard we grow (potato) and (tomato)
5.This museum exhibits the 18th-century (organ),(piano) and (grand piano)
6.Why do financial (crisis) happen?
7.I want to read Shakespeare's (play), both (tragedy) and (comedy)
8.(Roof) on houses vary in geometry , method of ventilation and covering material
9.There are computer (disk) in those (box)
10. At the Geography lessons we study nature (phenomenon)