a. Dear Sir or Madam,

b. Dear Valued Customer,

c. To Whom It May Concern:

d. – （不要）

a. In this rainy season, we are glad that your company is thriving more than ever.

b. We hope this email finds you well in this rainy season.

c. We hope you are doing well in this rainy season.

d. – （不要）

a. Thank you very much for giving us special favor at all times.

b. Thank you for your business.

c. Thank you always for your business.

d. – （不要）

a. Well, this is to announce the launch of our new product.

b. Then, this time, we would like to inform you of the launch of our new product.

c. We recently launched a new product.

d. – （不要）

a. This information was sent to you in hopes of acquiring even more favor than before.

b. We humbly ask for more business than before.

c. Thank you for your continued business.

d. – （不要）

a. Cheers,

b. Best Regards,

c. Best,

d. – （不要）

a. Taro Yamada, President, Yamada Electronics K.K.

b. K.K. Yamada Electronics, Representative Director Taro Yamada

c. Representative Director Taro Yamada, K.K. Yamada Electronics

d. – （不要）