1) to sit-sitting(сесть)
2)to visit-visitting (посетить)
3)to check-cheking
4)to have-having (иметь)
5) to buy-bought (купить)
6) to do-doing (делать)
7) to work-working(работать)
8)to invite-invitting
9) to look-looking(смотреть)
4.10
2) She don't sitting at the table.
3) They are not going to buy this computer.
4) They are not going lunch in the ofice