The phrase "appreciate your efforts" is correct and usable in written English. You can use it to show appreciation for someone who has worked hard in order to accomplish something. Example: "I wanted to let you know that I truly appreciate your efforts in organizing this event."
We all appreciate your efforts.
"No, thanks, but I do appreciate your efforts.
And then finally, it never hurts in terms of reward to actually have the students appreciate your efforts.
"I appreciate your efforts, and look forward to working with you so that the Congress can complete health care reform by October".
Their English is a joy to hear because of how colloquial and idiomatic it is, but they appreciate your efforts with Icelandic.
I greatly appreciate your efforts but the great majority do not read newspapers and magazines to inform themselves on the latest developments in the fields of business and economics.
I much appreciate your effort, wit and insights.
I appreciate your effort to correct my mis-identification.
I really appreciate your effort in this post and you have benefited others and me by enhancing my knowledge.
I appreciate your effort to reach out and communicate your memories and thoughts re ugly events that occurred so many years ago.
Lance Helgeson, Chicago: I appreciate your effort to highlight some of the bravery and courage U.S. troops exhibit every day in Iraq.
Being a terminologist, I care about word choice. Ludwig simply helps me pick the best words for any translation. Five stars!
Maria Pia Montoro
Terminologist and Q/A Analyst @ Translation Centre for the Bodies of the European Union