1. I am writing to ask about sth 我写这封信为了…
I am writing to ask about conference facilities at your London hotel.
2. We would like to do sth… 我们想要...
We would like to demonstrate some of our equipment and present information about our products to our guests.
3. I would be grateful if you could do sth 如果你能做什么，我们将非常感激
I would be grateful if you could send me your specific requirements.