Нужна помощь с английским (грамматика)

Question

I.Откройте скобки, употребляя причастие I или герундий.

Dear Sirs.

We have pleasure in inform you of the merger of our company with NIKKO
Photographic company coming into effect on 1 December 20... The new
company will be known as Universal TOYO OPTICS with head offices in
Tokyo and Osaka. Established in 1983, NIKKO Photo-graphic are well-known
as manufactures of first-class optical equipment and instruments. (Buying) their lenses for over 30 years we intend to cooperate closely. As a
result of this merger we shall be able to offer you a larger range of
cameras, projectors and optical equipment. Our new catalogue is
enclosed. No further changes will be made. We look forward to (to
maintaining) our business and personal ties and (continuing) the prompt
service that our customers appreciate. Please give us an opportunity of
(supplying) you with our extended range of goods.

Юлия Ильичева · Accepted Answer

We have pleasure in inform you of the merger of our company with NIKKO 
Photographic company coming into effect on 1 December 20... The new 
company will be known as Universal TOYO OPTICS with head offices in 
Tokyo and Osaka. Established in 1983, NIKKO Photo-graphic are well-known 
as manufactures of first-class optical equipment and instruments. (Buying) their lenses for over 30 years we intend to cooperate closely. As a
 result of this merger we shall be able to offer you a larger range of
 cameras, projectors and optical equipment. Our new catalogue is 
enclosed. No further changes will be made. We look forward to (to 
maintaining) our business and personal ties and (continuing) the prompt 
service that our customers appreciate. Please give us an opportunity of 
(supplying) you with our extended range of goods.